885 results on '"Masakazu, Yamamoto"'
Search Results
52. Data from Long-term Vaccination with Multiple Peptides Derived from Cancer-Testis Antigens Can Maintain a Specific T-cell Response and Achieve Disease Stability in Advanced Biliary Tract Cancer
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Masakazu Yamamoto, Kazuyoshi Takeda, Takehiro Ohta, Norimasa Matsushita, Ryuji Okuyama, Yoshihito Kotera, Nobuhiro Takeshita, and Atsushi Aruga
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Purpose: The prognosis of patients with advanced biliary tract cancer (BTC) is extremely poor and there are only a few standard treatments. We conducted a phase I trial to investigate the safety, immune response, and antitumor effect of vaccination with four peptides derived from cancer-testis antigens, with a focus on their fluctuations during long-term vaccination until the disease had progressed.Experimental Design: Nine patients with advanced BTC who had unresectable tumors and were refractory to standard chemotherapy were enrolled. HLA-A*2402–restricted epitope peptides, lymphocyte antigen 6 complex locus K, TTK protein kinase, insulin-like growth factor-II mRNA-binding protein 3, and DEP domain containing 1 were vaccinated subcutaneously once a week at doses of 0.5, 1, or 2 mg and continued until disease progression. The adverse events were assessed by Common Terminology Criteria for Adverse Events and the immune response was monitored by an enzyme-linked immunospot assay or by flow cytometry. The clinical effects observed were tumor response, progression-free survival (PFS), and overall survival (OS).Results: Four-peptide vaccination was well tolerated. No grade 3 or 4 adverse events were observed. Peptide-specific T-cell immune responses were observed in seven of nine patients and clinical responses were observed in six of nine patients. The median PFS and OS were 156 and 380 days. The injection site reaction and CTL induction seemed to be prognostic factors of both PFS and OS.Conclusions: Four-peptide vaccination was well tolerated and seemed to provide some clinical benefit to some patients. These immunologic and clinical responses were maintained over the long term through continuous vaccinations. Clin Cancer Res; 19(8); 2224–31. ©2013 AACR.
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- 2023
53. Supplementary Figure 1 from Long-term Vaccination with Multiple Peptides Derived from Cancer-Testis Antigens Can Maintain a Specific T-cell Response and Achieve Disease Stability in Advanced Biliary Tract Cancer
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Masakazu Yamamoto, Kazuyoshi Takeda, Takehiro Ohta, Norimasa Matsushita, Ryuji Okuyama, Yoshihito Kotera, Nobuhiro Takeshita, and Atsushi Aruga
- Abstract
PDF File - 111K, Immunologic monitoring of each peptide-specific T cell response in each patient.
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- 2023
54. Supplementary Figure Legends from Long-term Vaccination with Multiple Peptides Derived from Cancer-Testis Antigens Can Maintain a Specific T-cell Response and Achieve Disease Stability in Advanced Biliary Tract Cancer
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Masakazu Yamamoto, Kazuyoshi Takeda, Takehiro Ohta, Norimasa Matsushita, Ryuji Okuyama, Yoshihito Kotera, Nobuhiro Takeshita, and Atsushi Aruga
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PDF File - 23K, Legends for Figures 1 and 2.
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- 2023
55. Supplementary Figure 2 from Long-term Vaccination with Multiple Peptides Derived from Cancer-Testis Antigens Can Maintain a Specific T-cell Response and Achieve Disease Stability in Advanced Biliary Tract Cancer
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Masakazu Yamamoto, Kazuyoshi Takeda, Takehiro Ohta, Norimasa Matsushita, Ryuji Okuyama, Yoshihito Kotera, Nobuhiro Takeshita, and Atsushi Aruga
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PDF File - 125K, An algorithm to define the responses of antigen-specific T cells by using the ELISPOT assay.
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- 2023
56. Clinical outcomes of organ‐preserving pancreatectomy for benign or low‐grade malignant pancreatic tumors: A multicenter nationwide survey in Japan
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Yukio Asano, Hiroyuki Kato, Satoshi Arakawa, Masahiro Ito, Takukazu Nagakawa, Akimasa Nakao, Tetsuo Ohta, Hiroki Yamaue, Masakazu Yamamoto, Sohei Satoi, Yasuhiro Kodera, Yoshifumi Takeyama, Masayuki Ohtsuka, Itaru Endo, Tadahiro Takada, and Akihiko Horiguchi
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Pancreatic Neoplasms ,Pancreatic Fistula ,Pancreatectomy ,Postoperative Complications ,Treatment Outcome ,Japan ,Hepatology ,Quality of Life ,Humans ,Surgery ,Pancreaticoduodenectomy ,Retrospective Studies - Abstract
Whether organ-preserving pancreatic surgery has an advantage in postoperative short- and long-term outcomes or not is still unknown because only small case series studies have been available to date. In this multicenter retrospective study, we aimed to elucidate the clinical advantage and disadvantage of organ-preserving pancreatectomy among patients with low-grade malignant pancreatic tumors and benign pancreatic diseases.We included patients diagnosed with benign or low-malignant pancreatic tumor who underwent pancreaticoduodenectomy (PD) in 621 cases, duodenum-preserving pancreatic head resection (DPPHR) in 31 cases, middle pancreatectomy (MP) in 148 cases, distal pancreatectomy (DP) in 814 cases, and spleen-preserving distal pancreatectomy (SPDP) in 259 cases between January 1, 2013, and December 31, 2017. Preoperative backgrounds, surgical outcomes and pre- and postoperative (3, 6, 12, 24, and 36 months) nutritional status were compared between these procedures.In terms of short-term outcomes, the incidence of pancreatic fistula in patients who underwent MP was significantly higher than in patients with standard pancreatectomy. As for the long-term pancreatic functions in the cases of head or body lesion, both exocrine and endocrine functions after MP were significantly favorable compared with the PD group from 3 to 36 months after surgery. In pancreatic body or tail lesion, significant advantage of endocrine function, but not exocrine function, was found in the MP group compared to standard DP at all time points.MP may contribute to the improvement of postoperative quality of life for patients with pancreatic body low-malignant tumors, rather than PD or DP; however, reducing the incidence of short-term complications such as pancreatic fistula is a future challenge.
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- 2022
57. Individual patient data meta-analysis of adjuvant gemcitabine-based chemotherapy for biliary tract cancer: combined analysis of the BCAT and PRODIGE-12 studies
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Julien Edeline, Satoshi Hirano, Aurélie Bertaut, Masaru Konishi, Meher Benabdelghani, Katsuhiko Uesaka, Jérôme Watelet, Masayuki Ohtsuka, Pascal Hammel, Yuji Kaneoka, Jean-Paul Joly, Masakazu Yamamoto, Laure Monard, Yoshiyasu Ambo, Christophe Louvet, Masahiko Ando, David Malka, Masato Nagino, Jean-Marc Phelip, and Tomoki Ebata
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Cancer Research ,Bile Ducts, Intrahepatic ,Biliary Tract Neoplasms ,Bile Duct Neoplasms ,Oncology ,Chemotherapy, Adjuvant ,Antineoplastic Combined Chemotherapy Protocols ,Humans ,Neoplasm Recurrence, Local ,Deoxycytidine ,Gemcitabine ,Randomized Controlled Trials as Topic - Abstract
Although gemcitabine-based chemotherapy is the standard of care for advanced biliary tract cancers (BTCs), adjuvant phase III studies (BCAT in Japan, PRODIGE 12 in France) failed to show benefit, possibly owing to fewer patients (n = 225 and n = 194) compared with the adjuvant capecitabine BILCAP trial (n = 447). We performed a combined analysis of both gemcitabine-based chemotherapy adjuvant studies.We performed individual patient data meta-analysis of all patients included in BCAT and PRODIGE 12. BCAT study randomised patients with extrahepatic cholangiocarcinoma to single-agent gemcitabine or observation. PRODIGE 12 randomised patients with all BTC subtypes to gemcitabine-oxaliplatin combination or observation. Combined analysis was performed using Kaplan-Meier curves and a Cox regression model stratified on the trial.Two hundred and twelve versus 207 patients were randomised in the gemcitabine-based chemotherapy versus observation arms. Baseline characteristics were balanced between arms. The median follow-up was 5.5 years. After 258 relapse-free survival (RFS) events, there was no difference in RFS (log-rank p = 0.45; hazard ratio [HR] = 0.91 [95% confidence interval [CI] 0.71-1.16]; p = 0.46). RFS rates at five years were 40.8% (95%CI: 33.9%-47.5%) for gemcitabine-based chemotherapy versus 36.6% (95%CI: 29.8%-43.4%) for observation. After 201 deaths, there was no difference in overall survival (OS) (log-rank p = 0.83; HR = 1.03 [95%CI: 0.78-1.35]; p = 0.85). OS rates at five years were 50.5% (95%CI: 43.1%-57.4%) for gemcitabine-based chemotherapy versus 49.3% (95%CI: 41.6%-56.5%) for observation.With 419 patients included, this analysis did not show significant improvement in RFS and no trend in improvement in OS. Gemcitabine-based chemotherapy should not be used as an adjuvant treatment for BTC.
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- 2022
58. A case of pathologically complete response after preoperative chemotherapy in a pancreatic acinar cell carcinoma patient with portal vein tumor thrombosis
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Wataru Izumo, Ryota Higuchi, Toru Furukawa, Takehisa Yazawa, Shuichiro Uemura, Yukiko Takayama, Kyoko Shimizu, Katsutoshi Tokushige, Hiroto Egawa, and Masakazu Yamamoto
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Male ,Pancreatic Neoplasms ,Venous Thrombosis ,Carcinoma, Acinar Cell ,Portal Vein ,Antineoplastic Combined Chemotherapy Protocols ,Gastroenterology ,Humans ,General Medicine ,Aged - Abstract
Preoperative treatment is being proposed as a standard treatment for pancreatic ductal adenocarcinoma though few cases show a pathologically complete response. On the other hand, there is no consensus regarding preoperative chemotherapy for pancreatic acinar cell carcinoma (ACC). The present study described a rare case of ACC in the pancreatic head with portal vein tumor thrombosis (PVTT) treated with preoperative chemotherapy using modified FOLFIRINOX, which achieved a pathologically complete response. A 65-year-old man was referred for consideration of treatment strategy. Contrast-enhanced abdominal computed tomography revealed a pancreatic tumor and PVTT. The pancreatic tumor was diagnosed as ACC by an endoscopic ultrasound-guided fine-needle aspiration biopsy. Initially, the tumor was assessed as unresectable due to the presence of PVTT, and therefore, a chemotherapy using modified FOLFIRINOX was administered. After 14 courses of the chemotherapy, imaging studies revealed that the tumor and PVTT showed marked reduction in size; thus, the patient underwent pancreaticoduodenectomy with combined resection of the portal vein (PV). A pathological examination uncovered a complete degeneration of the primary tumor and the PV embolus without any residue of carcinoma. The patient did not receive adjuvant chemotherapy and survived with no evidence of recurrence for 33 months after surgery. The chemotherapy using modified FOLFIRINOX could give a complete response in patients with pancreatic ACC with PVTT.
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- 2022
59. Liver Resection for Hepatocellular Carcinoma with Tumor Thrombus in the Inferior Vena Cava or Right Atrium: A Large-scale Multicenter Survey Conducted in Japan
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Akihiko Ichida, Takashi Kokudo, Shingo Shimada, Etsuro Hatano, Shoji Kubo, Yutaro Kato, Yoshiya Ishikawa, Akira Mori, Hideo Baba, Yutaka Matsuyama, Itaru Endo, Hiroki Yamaue, Masakazu Yamamoto, Norihiro Kokudo, and Kiyoshi Hasegawa
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Surgery - Abstract
To clarify the short- and long-term postoperative outcomes and surgical indications for patients accompanied by hepatocellular carcinoma (HCC) with tumor thrombus (TT) in the inferior vena cava (IVC) or right atrium (RA).These patients are known to have an extremely poor prognosis; however, the postoperative outcomes have not been fully verified because of the rarity of this disease.We contacted 211 specialized centers in Japan and collected data on liver resection for HCC with TT in the IVC or RA from centers with experience performing surgery for such patients. The patient characteristics, operative procedures, and surgical outcomes were then analyzed.A total of 119 patients from 23 institutions were enrolled; 49 patients had TT in the IVC below the diaphragm (type I), 42 had TT in the IVC above the diaphragm (type II), and 28 had TT entering the RA (type III). The severity and frequency of postoperative complications did not differ among the three groups. There was one surgery-related death in the type III group. The median survival times were 2.47 years in the type I group, 1.77 years in the type II group, and 1.02 years in the type III group. A multivariate analysis identified an indocyanine green retention rate at 15 min15% and ≥3 tumors as prognostic factors affecting survival, while the use of cardiopulmonary bypass and ≥3 tumors were risk factors for recurrence.As the postoperative prognosis of patients with type I or type II disease and of patients with no risk factors is relatively good, surgery should be considered for these patient populations.
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- 2023
60. A patient with an intraductal papillary mucinous carcinoma with obstructive jaundice caused by a pancreato-biliary fistula
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Ryosuke IMAZATO, Shuji SUZUKI, Mitsugi SHIMODA, Jiro SHIMAZAKI, Yukio OSHIRO, Kiyotaka NISHIDA, Ryutaro UDO, and Masakazu YAMAMOTO
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- 2021
61. Minimally invasive anatomic liver resection: Results of a survey of world experts
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Mamoru Morimoto, Kazuteru Monden, Taiga Wakabayashi, Naoto Gotohda, Yuta Abe, Goro Honda, Mohammed Abu Hilal, Takeshi Aoki, Horacio J. Asbun, Giammauro Berardi, Albert C.Y. Chan, Rawisak Chanwat, Kuo‐Hsin Chen, Yajin Chen, Daniel Cherqui, Tan To Cheung, Ruben Ciria, David Fuks, David A. Geller, Ho‐Seong Han, Kiyoshi Hasegawa, Etsuro Hatano, Osamu Itano, Yukio Iwashita, Hironori Kaneko, Yutaro Kato, Ji Hoon Kim, Rong Liu, Santiago López‐Ben, Fernando Rotellar, Yoshihiro Sakamoto, Atsushi Sugioka, Tomoharu Yoshizumi, Keiichi Akahoshi, Felipe Alconchel, Shunichi Ariizumi, Andrea Benedetti Cacciaguerra, Manuel Durán, Alain García Vázquez, Nicolas Golse, Yoshihiro Miyasaka, Yasuhisa Mori, Satoshi Ogiso, Chikara Shirata, Federico Tomassini, Takeshi Urade, Hitoe Nishino, Filipe Kunzler, Shingo Kozono, Hiroaki Osakabe, Chie Takishita, Daisuke Ban, Taizo Hibi, Norihiro Kokudo, Masayuki Ohtsuka, Yuichi Nagakawa, Takao Ohtsuka, Minoru Tanabe, Masafumi Nakamura, Masakazu Yamamoto, Akihiko Tsuchida, and Go Wakabayashi
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Hepatology ,Surveys and Questionnaires ,Liver Neoplasms ,Hepatectomy ,Humans ,Laparoscopy ,Surgery - Abstract
Although the number of minimally invasive liver resections (MILRs) has been steadily increasing in many institutions, minimally invasive anatomic liver resection (MIALR) remains a complicated procedure that has not been standardized. We present the results of a survey among expert liver surgeons as a benchmark for standardizing MIALR.We administered this survey to 34 expert liver surgeons who routinely perform MIALR. The survey contained questions on personal experience with liver resection, inflow/outflow control methods, and identification techniques of intersegmental/sectional planes (IPs).All 34 participants completed the survey; 24 experts (70%) had more than 11 years of experience with MILR, and over 80% of experts had performed over 100 open resections and MILRs each. Regarding the methods used for laparoscopic or robotic anatomic resection, the Glissonean approach (GA) was a more frequent procedure than the hilar approach (HA). Although hepatic veins were considered essential landmarks, the exposure methods varied. The top three techniques that the experts recommended for identifying IPs were creating a demarcation line, indocyanine green negative staining method, and intraoperative ultrasound.Minimally invasive anatomic liver resection remains a challenging procedure; however, a certain degree of consensus exists among expert liver surgeons.
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- 2021
62. Evaluation of Early Prognostic Factors in Patients With Pancreatic Ductal Adenocarcinoma Receiving Gemcitabine Together With Nab-paclitaxel
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Wataru Izumo, Masahiro Shiihara, Ryota Higuchi, Shuichiro Uemura, Masakazu Yamamoto, Toru Furukawa, Yutaro Matsunaga, and Takehisa Yazawa
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Oncology ,medicine.medical_specialty ,Pancreatic ductal adenocarcinoma ,business.industry ,Internal medicine ,medicine ,In patient ,business ,Gemcitabine ,Research Article ,Nab-paclitaxel ,medicine.drug - Abstract
Background: Gemcitabine together with nab-paclitaxel (GnP) has been shown to improve outcomes in patients with pancreatic ductal adenocarcinoma (PDAC). However, the predictive markers for treatment effects remain unclear. This study aimed to identify early prognostic factors in patients with PDAC receiving GnP. Patients and Methods: We analyzed 113 patients who received GnP for PDAC and evaluated the relationship between clinical factors and outcomes. Results: The median survival time (MST) was 1.2 years. In multivariate analysis, baseline carbohydrate antigen 19-9 (CA19-9) ≥747 U/ml [hazard ratio (HR)=1.9], baseline controlling nutrition status (CONUT) score ≥5 (HR=3.7) and changing rate of CA19-9 after two GnP cycles ≥0.69 (HR=3.7) were independent risk factors for poor prognosis. When examining outcomes according to pre-chemotherapeutic measurable factors (baseline CA19-9 and CONUT), the MSTs of patients with pre-chemotherapeutic zero risk factors (pre-low-risk group, n=63) and one or more risk factors (pre-high-risk group, n=50) were 1.7 and 0.65 years (p
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- 2021
63. Perihilar Cholangiocarcinoma - Novel Benchmark Values for Surgical and Oncological Outcomes From 24 Expert Centers
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Camila Hidalgo-Salinas, Ryota Higuchi, Elissaios Kontis, Eva Breuer, Ho-Seong Han, Andrea Ruzzenente, Jennifer A. Yonkus, Victor Lopez-Lopez, Warsan Ismail, Richard D. Schulick, Matteo Mueller, Masayuki Ohtsuka, Wojciech G. Polak, Kim C Wagner, René Adam, Keun Soo Ahn, Rory L. Smoot, Joon Seong Park, Karim Boudjema, Takashi Mizuno, Ana Gleisner, Masato Nagino, Tsukasa Takayashiki, Gregory J. Gores, Tiffany C.L. Wong, Johann Pratschke, Chaya Shwaartz, Pierre-Alain Clavien, Mizelle D'Silva, Fabian Bartsch, Constantino Fondevila, Hauke Lang, Takehiro Noji, Ulf P. Neumann, Ricardo Robles-Campos, Ganesh Gunasekaran, Masakazu Yamamoto, Olivier Soubrane, Francesca Ratti, Andreas Prachalias, Katsuhiko Uesaka, Joris I. Erdmann, Myron Schwartz, Pål-Dag Line, Christian Benzing, Luca Aldrighetti, Amelia J. Hessheimer, Jan Bednarsch, Karl J. Oldhafer, Koo Jeong Kang, Michelle L. de Oliveira, Charles de Ponthaud, Chung Mau Lo, Gonzalo Sapisochin, Heithem Jeddou, Lynn E Nooijen, Hyung Sun Kim, Noémie Ammar-Khodja, Teiichi Sugiura, Bas Groot Koerkamp, Alfredo Guglielmi, Satoshi Hirano, Giuseppe Fusai, Mueller, M., Breuer, E., Mizuno, T., Bartsch, F., Ratti, F., Benzing, C., Ammar-Khodja, N., Sugiura, T., Takayashiki, T., Hessheimer, A., Kim, H. S., Ruzzenente, A., Ahn, K. S., Wong, T., Bednarsch, J., D'Silva, M., Koerkamp, B. G., Jeddou, H., Lopez-Lopez, V., de Ponthaud, C., Yonkus, J. A., Ismail, W., Nooijen, L. E., Hidalgo-Salinas, C., Kontis, E., Wagner, K. C., Gunasekaran, G., Higuchi, R., Gleisner, A., Shwaartz, C., Sapisochin, G., Schulick, R. D., Yamamoto, M., Noji, T., Hirano, S., Schwartz, M., Oldhafer, K. J., Prachalias, A., Fusai, G. K., Erdmann, J. I., Line, P. -D., Smoot, R. L., Soubrane, O., Robles-Campos, R., Boudjema, K., Polak, W. G., Han, H. -S., Neumann, U. P., Lo, C. -M., Kang, K. J., Guglielmi, A., Park, J. S., Fondevila, C., Ohtsuka, M., Uesaka, K., Adam, R., Pratschke, J., Aldrighetti, L., De Oliveira, M. L., Gores, G. J., Lang, H., Nagino, M., Clavien, P. -A., and Surgery
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Adult ,Male ,medicine.medical_specialty ,Percentile ,Asia ,Time Factors ,MEDLINE ,outcomes ,High morbidity ,Postoperative Complications ,SDG 3 - Good Health and Well-being ,Diabetes mellitus ,Internal medicine ,benchmarks ,80 and over ,Medicine ,Hepatectomy ,Humans ,Perihilar Cholangiocarcinoma ,Aged ,Retrospective Studies ,Aged, 80 and over ,business.industry ,CCI ,Mortality rate ,Middle Aged ,medicine.disease ,surgical complications ,major liver surgery ,United States ,Europe ,Benchmarking ,Editorial ,Bile Duct Neoplasms ,Benchmark (computing) ,Surgery ,Female ,business ,Body mass index ,perihilar cholangiocarcinoma ,Follow-Up Studies ,Klatskin Tumor - Abstract
OBJECTIVE: The aim of this study was to define robust benchmark values for the surgical treatment of perihilar cholangiocarcinomas (PHC) to enable unbiased comparisons. BACKGROUND: Despite ongoing efforts, postoperative mortality and morbidity remains high after complex liver surgery for PHC. Benchmark data of best achievable results in surgical PHC treatment are however still lacking. METHODS: This study analyzed consecutive patients undergoing major liver surgery for PHC in 24 high-volume centers in 3 continents over the recent 5-year period (2014-2018) with a minimum follow-up of 1 year in each patient. Benchmark patients were those operated at high-volume centers (≥50 cases during the study period) without the need for vascular reconstruction due to tumor invasion, or the presence of significant co-morbidities such as severe obesity (body mass index ≥35), diabetes, or cardiovascular diseases. Benchmark cutoff values were derived from the 75th or 25th percentile of the median values of all benchmark centers. RESULTS: Seven hundred eight (39%) of a total of 1829 consecutive patients qualified as benchmark cases. Benchmark cut-offs included: R0 resection ≥57%, postoperative liver failure (International Study Group of Liver Surgery): ≤35%; in-hospital and 3-month mortality rates ≤8% and ≤13%, respectively; 3-month grade 3 complications and the CCI: ≤70% and ≤30.5, respectively; bile leak-rate: ≤47% and 5-year overall survival of ≥39.7%. Centers operating mostly on complex cases disclosed better outcome including lower post-operative liver failure rates (4% vs 13%; P = 0.002). Centers from Asia disclosed better outcomes. CONCLUSION: Surgery for PHC remains associated with high morbidity and mortality with now the availability of benchmark values covering 21 outcome parameters, which may serve as key references for comparison in any future analyses of individuals, group of patients or centers.
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- 2021
64. A Case of Postoperative Recurrence of Primary Malignant Melanoma of the Esophagus in the Liver with Complete Response with Nivolumab Therapy
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Harushi Osugi, Yosuke Yagawa, Shinsuke Maeda, Kyohei Ogawa, Hiromi Onizuka, Kenji Kudo, Yukinori Toyoshima, Masakazu Yamamoto, and Kosuke Narumiya
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Oncology ,medicine.medical_specialty ,business.industry ,Melanoma ,Gastroenterology ,medicine.disease ,medicine.anatomical_structure ,Internal medicine ,Medicine ,Surgery ,Esophagus ,Nivolumab ,business ,Complete response - Published
- 2021
65. Automated recognition of objects and types of forceps in surgical images using deep learning
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Michio Itabashi, Takahiro Okamoto, Shingo Kameoka, Masakazu Yamamoto, Yoshiko Bamba, and Shimpei Ogawa
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Colon ,Mathematics and computing ,Computer science ,Science ,Forceps ,education ,Video Recording ,Convolutional neural network ,Article ,Pattern Recognition, Automated ,Intraoperative Period ,Deep Learning ,Medical research ,Software Design ,Image Processing, Computer-Assisted ,Surgical skills ,Humans ,Computer vision ,Digestive System Surgical Procedures ,Clip forceps ,Cancer ,Surgeons ,Multidisciplinary ,Grasping forceps ,business.industry ,Deep learning ,Rectum ,Gastroenterology ,Surgical Instruments ,Motor Skills ,Medicine ,Clinical Competence ,Artificial intelligence ,Precision and recall ,business ,Professional skills - Abstract
Background: Analysis of operative data with convolutional neural networks (CNNs) is expected to improve the knowledge and professional skills of surgeons. Identification of objects in videos recorded during surgery can be used for surgical skill assessment and surgical navigation. The objectives of this study were to recognize objects and types of forceps in surgical videos acquired during colorectal surgeries and evaluate detection accuracy.Methods: Images (n=1818) were extracted from 11 surgical videos for model training, and another 500 images were extracted from 6 additional videos for validation. The following 5 types of forceps were selected for annotation: ultrasonic scalpel, grasping, clip, angled (Maryland and right-angled), and spatula. IBM Visual Insights software was used, which incorporates the most popular open-source deep-learning CNN frameworks.Results: In total, 1039/1062 (97.8%) forceps were correctly identified among 500 test images. Calculated recall and precision values were as follows: grasping forceps, 98.1% and 98.0%; ultrasonic scalpel, 99.4% and 93.9%; clip forceps, 96.2% and 92.7%; angled forceps, 94.9% and 100%; and spatula forceps, 98.1% and 94.5%, respectively.Conclusions: Forceps recognition can be achieved with high accuracy using deep-learning models, providing the opportunity to evaluate how forceps are used in various operations.
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- 2021
66. Palovarotene reduces heterotopic ossification in juvenile FOP mice but exhibits pronounced skeletal toxicity
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John B Lees-Shepard, Sarah-Anne E Nicholas, Sean J Stoessel, Parvathi M Devarakonda, Michael J Schneider, Masakazu Yamamoto, and David J Goldhamer
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fibrodysplasia ossificans progressiva ,palovarotene ,fibro/adipogenic progenitor ,heterotopic ossification ,activin A ,ACVR1 ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
Fibrodysplasia ossificans progressiva (FOP) is a rare genetic disorder characterized by debilitating heterotopic ossification (HO). The retinoic acid receptor gamma agonist, palovarotene, and antibody-mediated activin A blockade have entered human clinical trials, but how these therapeutic modalities affect the behavior of pathogenic fibro/adipogenic progenitors (FAPs) is unclear. Using live-animal luminescence imaging, we show that transplanted pathogenic FAPs undergo rapid initial expansion, with peak number strongly correlating with HO severity. Palovarotene significantly reduced expansion of pathogenic FAPs, but was less effective than activin A inhibition, which restored wild-type population growth dynamics to FAPs. Palovarotene pretreatment did not reduce FAPs’ skeletogenic potential, indicating that efficacy requires chronic administration. Although palovarotene inhibited chondrogenic differentiation in vitro and reduced HO in juvenile FOP mice, daily dosing resulted in aggressive synovial joint overgrowth and long bone growth plate ablation. These results highlight the challenge of inhibiting pathological bone formation prior to skeletal maturation.
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- 2018
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67. Lateral pelvic lymph nodes for rectal cancer: A review of diagnosis and management
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Yuji Inoue, Kimitaka Tani, Hiroka Kondo, Yoshiko Bamba, Shimpei Ogawa, Shigeki Yamaguchi, Ryosuke Nakagawa, Hisako Aihara, Masakazu Yamamoto, Kurodo Koshino, Michio Itabashi, and Takeshi Ohki
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medicine.medical_specialty ,Colorectal cancer ,medicine.medical_treatment ,Lateral pelvic lymph node metastasis ,Metastasis ,Lateral pelvic lymph node dissection ,Diagnosis ,medicine ,Risk factor ,Rectal cancer ,Lymph node ,Pelvis ,medicine.diagnostic_test ,Radiotherapy ,business.industry ,Gastroenterology ,Magnetic resonance imaging ,Minireviews ,medicine.disease ,Radiation therapy ,Treatment ,Dissection ,medicine.anatomical_structure ,Oncology ,Radiology ,business - Abstract
The current status and future prospects for diagnosis and treatment of lateral pelvic lymph node (LPLN) metastasis of rectal cancer are described in this review. Magnetic resonance imaging (MRI) is recommended for the diagnosis of LPLN metastasis. A LPLN-positive status on MRI is a strong risk factor for metastasis, and evaluation by MRI is important for deciding treatment strategy. LPLN dissection (LPLD) has an advantage of reducing recurrence in the lateral pelvis but also has a disadvantage of complications; therefore, LPLD may not be appropriate for cases that are less likely to have LPLN metastasis. Radiation therapy (RT) and chemoradiation therapy (CRT) have limited effects in cases with suspected LPLN metastasis, but a combination of preoperative CRT and LPLD may improve the treatment outcome. Thus, RT and CRT plus selective LPLD may be a rational strategy to omit unnecessary LPLD and produce a favorable treatment outcome.
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- 2021
68. The outcomes of thrombotic microangiopathy after liver transplantation: A nationwide survey in Japan
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Yasutsugu Takada, Masakazu Yamamoto, Susumu Eguchi, Hiroki Yamaue, and Mitsuhisa Takatsuki
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medicine.medical_specialty ,Multivariate analysis ,Thrombotic microangiopathy ,medicine.medical_treatment ,Liver transplantation ,urologic and male genital diseases ,Gastroenterology ,Primary sclerosing cholangitis ,Japan ,hemic and lymphatic diseases ,Internal medicine ,Living Donors ,medicine ,Humans ,Renal replacement therapy ,neoplasms ,Retrospective Studies ,Cause of death ,Hepatology ,Thrombotic Microangiopathies ,business.industry ,medicine.disease ,female genital diseases and pregnancy complications ,digestive system diseases ,Liver Transplantation ,Transplantation ,Hepatocellular carcinoma ,Surgery ,business - Abstract
Background Although thrombotic microangiopathy (TMA) is recognized as one of the poor-prognosis factors after liver transplantation, the precise outcome of TMA is unclear. We sought to elucidate the factors affecting the outcome of TMA after liver transplantation in Japan, based on the data from a nationwide survey. Methods One hundred cases of post-transplant TMA were accumulated from 17 Japanese centers of which 2 cases were excluded because the cause of death was obviously not related to TMA (recurrence of original diseases as primary sclerosing cholangitis and hepatocellular carcinoma), and remaining 98 cases were enrolled in this study. The patient survival after the development of TMA and the factors that affected the patients' outcomes were retrospectively analyzed. Results All cases were living-donor liver transplant cases, and the 1-, 3-, and 5-year patient survival rates after transplantation were 66.9%, 64.6%, and 62.2%, respectively. In a multivariate analysis, the requirement of renal replacement therapy during TMA treatment was the only factor that was significantly related to poor outcome after the development of TMA. Conclusion The outcomes of TMA were generally poor. The progression of renal dysfunction despite intensive treatment might be the only factor related to the poor prognosis after the development of TMA.
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- 2021
69. How to prevent contamination with Candida albicans during the fabrication of transplantable oral mucosal epithelial cell sheets
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Ryo Takagi, Shinichiro Kobayashi, Masayuki Yamato, Toshiyuki Owaki, Yoshiyuki Kasai, Takahiro Hosoi, Yusuke Sakai, Kengo Kanetaka, Tokutaro Minamizato, Asuka Minematsu, Makoto Kondo, Nobuo Kanai, Naoyuki Yamaguchi, Kazuhiro Nagai, Yasushi Miyazaki, Naoya Takeda, Fumio Fukai, Izumi Asahina, Taiga Miyazaki, Shigeru Kohno, Masakazu Yamamoto, Kazuhiko Nakao, Susumu Eguchi, and Teruo Okano
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Amphotericin B ,Candida albicans ,Oral mucosal epithelial cell ,Medicine (General) ,R5-920 ,Cytology ,QH573-671 - Abstract
We have utilized patients' own oral mucosa as a cell source for the fabrication of transplantable epithelial cell sheets to treat limbal stem cell deficiency and mucosal defects after endoscopic submucosal dissection of esophageal cancer. Because there are abundant microbiotas in the human oral cavity, the oral mucosa was sterilized and 40 μg/mL gentamicin and 0.27 μg/mL amphotericin B were added to the culture medium in our protocol. Although an oral surgeon carefully checked each patient's oral cavity and although candidiasis was not observed before taking the biopsy, contamination with Candida albicans (C. albicans) was detected in the conditioned medium during cell sheet fabrication. After adding 1 μg/mL amphotericin B to the transportation medium during transport from Nagasaki University Hospital to Tokyo Women's Medical University, which are 1200 km apart, no proliferation of C. albicans was observed. These results indicated that the supplementation of transportation medium with antimycotics would be useful for preventing contamination with C. albicans derived from the oral mucosa without hampering cell proliferation.
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- 2015
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70. Validation study of the JSHBPS nomogram for patients with colorectal liver metastases who underwent hepatic resection in the recent era - a nationwide survey in Japan
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Toru, Beppu, Kensuke, Yamamura, Katsunori, Sakamoto, Goro, Honda, Shin, Kobayashi, Itaru, Endo, Kiyoshi, Hasegawa, Kenjiro, Kotake, Michio, Itabashi, Yojiro, Hashiguchi, Yoshihito, Kotera, Tatsuro, Yamaguchi, Soichiro, Natsume, Ken, Tabuchi, Hirotoshi, Kobayashi, Kensei, Yamaguchi, Satoshi, Morita, Ken, Kikuchi, Masaru, Miyazaki, Kenichi, Sugihara, Masakazu, Yamamoto, and Keiichi, Takahashi
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Hepatology ,Surgery - Abstract
The Japanese Society of Hepato-Biliary-Pancreatic Surgery (JSHBPS) nomogram was developed to predict disease-free survival in patients with colorectal liver metastases (CRLM) undergoing upfront hepatectomy. However, the utility of the nomogram in patients with resected CRLM remains unknown in the current situation in which treatment strategies are changing with advances in drugs.Patients in the initial nomogram cohort (n = 727) and validation cohort (n = 2225) were divided into the upfront hepatectomy and preoperative chemotherapy groups. The nomogram was validated by measuring calibration and discrimination in the two cohorts. Calibration curves were plotted, and survival probabilities were compared. Finally, to quantify the discrimination power, we estimated the concordance index (C-index).In the upfront hepatectomy group, the C-index was 0.63, the suitable cutoff value of the Beppu score was 7, and adjuvant chemotherapy was significantly effective limited to high-risk patients (Beppu score ≥7). The C-index was 0.56 in the preoperative chemotherapy group.The JSHBPS nomogram remains beneficial for patients undergoing upfront hepatectomy in the recent era but is less effective for patients undergoing hepatectomy after chemotherapy. Patients with a Beppu score ≥7 showed high-risk recurrence, and adjuvant chemotherapy should be recommended for these patients.
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- 2022
71. Incidental diagnosis of oxyuriasis through a colonoscopy
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Shigekazu Iguchi, Yuji Hirai, Yusuke Ainoda, Noriko Isoda, Hitomi Miura, Hiroto Egawa, Masakazu Yamamoto, and Ken Kikuchi
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Enterobius vermicularis ,Colonoscopy ,“Scotch-tape” test ,Oxyuriasis ,Infectious and parasitic diseases ,RC109-216 - Published
- 2016
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72. Laparoscopic Hepatectomy: Current State in Japan Based on the 4th Nationwide Questionnaire
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Yutaka Takahashi, Satoshi Katagiri, Shun-ichi Ariizumi, Yoshihito Kotera, Hiroto Egawa, Go Wakabayashi, Hironori Kaneko, and Masakazu Yamamoto
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Diseases of the digestive system. Gastroenterology ,RC799-869 - Abstract
Purpose. Since laparoscopic hepatectomy (LH) became covered by national health insurance in April 2010 in Japan, the numbers of applied cases and institutions performing it have increased and the indication has expanded. We surveyed the current state and safety of LH in Japan. Methods. A questionnaire survey was performed in 41 institutions related to the Japanese Endoscopic Liver Surgery Study Group and 747 institutions certified by the Japanese Society of Gastroenterological Surgery, and responses concerning all 2962 cases of LH performed by August 2011 were obtained. Results. The surgical procedure employed was hemihepatectomy in 234 (8%), segmentectomy in 88 (3%), left lateral segmentectomy in 434 (15%), segmentectomy in 156 (5%), and partial resection in 1504 (51%) cases. The approach was pure laparoscopy in 1835 (63%), hand-assisted laparoscopic surgery in 201 (7%), and laparoscopy-assisted surgery in 926 (31%). Regarding perioperative complications, surgery was switched to laparotomy in 59 (2.0%), reoperation was performed in 4 (0.1%), and surgery-related death occurred in 2 (0.07%). Intraoperative accidents occurred in 68 (2.3%), and postoperative complications developed in 94 (3.2%). Conclusions. When the selection of cases is appropriate, LH for liver diseases can be safely performed.
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- 2017
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73. Comparison of infectious complications after spleen preservation versus splenectomy during laparoscopic distal pancreatectomy for benign or low-grade malignant pancreatic tumors: A multicenter, propensity score-matched analysis
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Woohyung Lee, Dae Wook Hwang, Ho‐Seong Han, In Woong Han, Jin Seok Heo, Michiaki Unno, Masaharu Ishida, Hiroshi Tajima, Nobuyuki Nishizawa, Kohei Nakata, Yasuji Seyama, Yoshiya Isikawa, Ho Kyoung Hwang, Jin‐Young Jang, Taeho Hong, Joon Seong Park, Hee Joon Kim, Chi‐Young Jeong, Ippei Matsumoto, Hiroki Yamaue, Manabu Kawai, Masayuki Ohtsuka, Shugo Mizuno, Mitsuhiro Asakuma, Yuji Soejima, Teijiro Hirashita, Masayuki Sho, Yutaka Takeda, Jeong‐Ik Park, Yong Hoon Kim, Hwa Jung Kim, Masakazu Yamamoto, Itaru Endo, Masafumi Nakamura, and Yoo‐Seok Yoon
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Hepatology ,Surgery - Abstract
Previous studies have reported contrasting results regarding the advantages of spleen preservation during laparoscopic distal pancreatectomy (LDP) for preventing infectious complications.A total of 3787 patients who underwent LDP for benign or low-grade malignant pancreatic disease in 92 centers across Korea and Japan were included in this retrospective study. Postoperative infectious complications and other complications were compared between LDP with splenectomy (LDPS) and LDP with spleen preservation (LSPDP) by propensity score matching (PSM) analysis.After PSM, the LSPDP group had a lower rate of overall infectious complications (P = .079) and a significantly lower rate of intra-abdominal abscess (P = .014) compared with the LDPS group. Within the LSPDP group, the vessel preservation subgroup had a significantly higher rate of infectious complications (P = .002) compared with the vessel resection subgroup. Low-volume centers had a higher rate of intra-abdominal abscess than high-volume centers in the LSPDP group (P = .001) and the splenic vessel preservation subgroup (P = .003).Spleen preservation in LDP for benign or borderline malignant pancreatic diseases was advantageous in lowering the risk of infectious complications, specifically intra-abdominal abscess. However, the risk of intra-abdominal abscess may differ according to the level of surgeon's experience.
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- 2022
74. Development, validation, and comparison of a nomogram based on radiologic findings for predicting malignancy in intraductal papillary mucinous neoplasms of the pancreas: An international multicenter study
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Hyung Il Seo, Michael D. Kluger, Ho-Seong Han, Wookyeong Song, Wonho Choo, Alex B. Blair, Wooil Kwon, Woo Jung Lee, Taesung Park, Nadine C.M. van Huijgevoort, Goro Honda, Takashi Hatori, Ching-Yao Yang, Shin E. Wang, Hyeong Seok Kim, Ki Byung Song, Satoshi Hirano, Hongbeom Kim, Tsutomu Fujii, Matthias Löhr, Yoo Seok Yoon, Song Cheol Kim, Yasushi Hashimoto, Hiroki Yamaue, Fuyuhiko Motoi, Marc G. Besselink, Masayuki Sho, Marco Del Chiaro, Jin He, Dong Wook Choi, Seong Ho Choi, Chang Moo Kang, Hiroaki Nagano, Hee Chul Yu, Yinmo Yang, Jin Seok Heo, Ippei Matsumoto, Sungyoung Lee, Wenhui Lou, Yi Ming Shyr, Christopher L. Wolfgang, Seungyeoun Lee, Yasuhiro Shimizu, Yuichi Nagakawa, Roberto Salvia, Jin-Young Jang, Jae Do Yang, Sang Geol Kim, Claudio Bassi, Youngmin Han, Sohei Satoi, Gloria H. Su, Jun Chul Chung, Giovanni Marchegiani, Masakazu Yamamoto, Roberto Valente, Seiko Hirono, Surgery, CCA - Imaging and biomarkers, CCA - Cancer Treatment and Quality of Life, Amsterdam Gastroenterology Endocrinology Metabolism, and Graduate School
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medicine.medical_specialty ,genetic structures ,urologic and male genital diseases ,Malignancy ,nomogram ,03 medical and health sciences ,0302 clinical medicine ,medicine ,cancer ,Cyst ,Pancreatic duct ,Hepatology ,Receiver operating characteristic ,business.industry ,Nomogram ,medicine.disease ,radiology ,medicine.anatomical_structure ,intraductal papillary mucinous neoplasms of the pancreas ,Dysplasia ,030220 oncology & carcinogenesis ,Cohort ,030211 gastroenterology & hepatology ,Surgery ,Radiology ,Pancreas ,business ,malignancy prediction - Abstract
Background Although we previously proposed a nomogram to predict malignancy in intraductal papillary mucinous neoplasms (IPMN) and validated it in an external cohort, its application is challenging without data on tumor markers. Moreover, existing nomograms have not been compared. This study aimed to develop a nomogram based on radiologic findings and to compare its performance with previously proposed American and Korean/Japanese nomograms. Methods We recruited 3708 patients who underwent surgical resection at 31 tertiary institutions in eight countries, and patients with main pancreatic duct > 10 mm were excluded. To construct the nomogram, 2606 patients were randomly allocated 1:1 into training and internal validation sets, and area under the receiver operating characteristics curve (AUC) was calculated using 10-fold cross validation by exhaustive search. This nomogram was then validated and compared to the American and Korean/Japanese nomograms using 1102 patients. Results Among the 2606 patients, 90 had main-duct type, 900 had branch-duct type, and 1616 had mixed-type IPMN. Pathologic results revealed 1628 low-grade dysplasia, 476 high-grade dysplasia, and 502 invasive carcinoma. Location, cyst size, duct dilatation, and mural nodule were selected to construct the nomogram. AUC of this nomogram was higher than the American nomogram (0.691 vs. 0.664, p = 0.014) and comparable with the Korean/Japanese nomogram (0.659 vs 0.653, p = 0.255). Conclusions A novel nomogram based on radiologic findings of IPMN is competitive for predicting risk of malignancy. This nomogram would be clinically helpful in circumstances where tumor markers are not available. The nomogram is freely available at http://statgen.snu.ac.kr/software/nomogramIPMN.
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- 2021
75. The utility of liver transplantation to treat acute liver failure caused by adult-onset Still’s disease: case reports
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Masayoshi Harigai, Hiroto Egawa, Yuri Ogasawara, Tomomi Kogiso, Makiko Taniai, Akiko Omori, Yoshihito Kotera, Takaomi Sagawa, Katsutoshi Tokushige, Eri Sugano, Masakazu Yamamoto, and Naoko Konda
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Adult ,medicine.medical_specialty ,Prednisolone ,medicine.medical_treatment ,Encephalopathy ,Liver transplantation ,Gastroenterology ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,Humans ,Glucocorticoids ,Aged ,Subacute thyroiditis ,business.industry ,digestive, oral, and skin physiology ,Liver failure ,General Medicine ,Liver Failure, Acute ,Middle Aged ,Hepatology ,medicine.disease ,Colorectal surgery ,Liver Transplantation ,030220 oncology & carcinogenesis ,Female ,030211 gastroenterology & hepatology ,business ,Still's Disease, Adult-Onset ,Abdominal surgery ,medicine.drug - Abstract
Adult-onset Still’s disease (AOSD) is an inflammatory condition commonly complicated by mild liver dysfunction. However, severe liver failure is rarely reported. We report three cases of severe acute hepatic failure (ALF) associated with AOSD. We encountered three cases of acute liver failure (ALF) with encephalopathy. Case 1 was a 75-year-old female, who was started on a steroid (prednisolone, PSL) to treat AOSD; this was gradually tapered. Two months later, severe ALF developed. She died despite an increase in the PSL dose and artificial liver support. Case 2 was a 26-year-old-female taking PSL 30 mg/day to treat subacute thyroiditis. PSL was tapered, and she received methyl PSL pulse therapy and artificial liver support, but this did not cure the ALF. Liver transplantation (LT) was performed 25 days later. Three years later, the same symptoms were observed and we diagnosed AOSD. Case 3 was a 56-year-old-female who met the AOSD criteria. PSL 50 mg/day was started and then tapered. Methyl PSL pulse therapy was prescribed to treat hemophagocytic syndrome, but she required LT on hospital day 13. In AOSD cases, ALF is rarely complicated; urgent LT should be considered only for patients with AOSD-related severe ALF.
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- 2021
76. Impact of the controlling nutritional status score on severe postoperative complications of pancreaticoduodenectomy for pancreatic cancer
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Ryota Higuchi, Wataru Izumo, Masahiro Shiihara, Takehisa Yazawa, Masakazu Yamamoto, Toru Furukawa, and Shuichiro Uemura
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medicine.medical_specialty ,medicine.medical_treatment ,Nutritional Status ,Pancreaticoduodenectomy ,03 medical and health sciences ,Postoperative Complications ,0302 clinical medicine ,Internal medicine ,Pancreatic cancer ,medicine ,Humans ,Risk factor ,Retrospective Studies ,business.industry ,Postoperative complication ,Vascular surgery ,Prognosis ,medicine.disease ,Pancreatic Neoplasms ,Cardiothoracic surgery ,030220 oncology & carcinogenesis ,030211 gastroenterology & hepatology ,Surgery ,Complication ,business ,Abdominal surgery - Abstract
The controlling nutritional status (CONUT) score is a useful biomarker to evaluate undernutrition. However, there have been few reports describing the correlation between postoperative complications and the CONUT score for pancreatic cancer. Therefore, this study aimed to assess the impact of the CONUT score on the postoperative complications of pancreaticoduodenectomy (PD) in patients with pancreatic cancer. We retrospectively analyzed 206 consecutive patients with pancreatic cancer who underwent PD over a 12-year duration at our institution. The patients were divided into two groups based on preoperative CONUT scores; their clinicopathological characteristics and surgical outcomes were compared. Furthermore, we compared the CONUT score with preoperative clinical factors and several nutritional biomarkers for postoperative complications using univariate and multivariate analyses. Postoperative complications of Clavien–Dindo grade ≥ IIIa and those of Clavien–Dindo grade ≥ IIIb occurred in 29 (14.1%) and 9 (4.4%) patients, respectively. The high CONUT score (≥5) group indicated that patients with an undernutrition status had a higher postoperative complication rate, poorer relapse-free survival, and overall survival rates than the low CONUT score (≤4) group. Among preoperative clinical factors, a high CONUT score was an independent risk factor for severe postoperative complications. The CONUT score may be a useful parameter in the identification of patients undergoing pancreatic surgery who are susceptible to postoperative complications.
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- 2021
77. Mortality, morbidity, and failure to rescue in hepatopancreatoduodenectomy: An analysis of patients registered in the National Clinical Database in Japan
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Norihiro Kokudo, Takafumi Kumamoto, Yasuyuki Seto, Masaru Miyazaki, Yuki Homma, Masato Nagino, Akihiko Horiguchi, Tomoo Kosuge, Norimichi Hirahara, Itaru Endo, Go Wakabayashi, Satoshi Hirano, Fumihiko Miura, Masaki Mori, Ryusei Matsuyama, Hiroki Yamaue, Yuko Kitagawa, Masakazu Yamamoto, Hiroyuki Yamamoto, and Hiroaki Miyata
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Certification ,Future studies ,Blood transfusion ,Failure to rescue ,Databases, Factual ,medicine.medical_treatment ,030230 surgery ,computer.software_genre ,Logistic regression ,03 medical and health sciences ,Postoperative Complications ,0302 clinical medicine ,Hospital volume ,Japan ,medicine ,Hepatectomy ,Humans ,Hospital Mortality ,Hepatology ,Database ,business.industry ,Operative mortality ,Postoperative complication ,030220 oncology & carcinogenesis ,Surgery ,Morbidity ,business ,computer - Abstract
BACKGROUND The high operative mortality rate after hepatopancreatoduodenectomy (HPD) is still a major issue. The present study explored why operative mortality differs significantly due to hospital volume. METHOD Surgical case data were extracted from the National Clinical Database (NCD) in Japan from 2011 to 2014. Surgical procedures were categorized as major (≥2 sections) and minor (
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- 2021
78. Glissonean approach for hepatic inflow control in minimally invasive anatomic liver resection: A systematic review
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Mamoru, Morimoto, Federico, Tomassini, Giammauro, Berardi, Yasuhisa, Mori, Chikara, Shirata, Mohammed, Abu Hilal, Horacio J, Asbun, Daniel, Cherqui, Naoto, Gotohda, Ho-Seong, Han, Yutaro, Kato, Fernando, Rotellar, Atsushi, Sugioka, Masakazu, Yamamoto, Go, Wakabayashi, and Akihiko, Tsuchida
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medicine.medical_specialty ,Surgical approach ,Hepatology ,business.industry ,General surgery ,Liver Neoplasms ,Operative Time ,030230 surgery ,Resection ,03 medical and health sciences ,Dissection ,0302 clinical medicine ,Liver anatomy ,Blood loss ,030220 oncology & carcinogenesis ,Hepatectomy ,Humans ,Medicine ,Operative time ,Laparoscopy ,Surgery ,business - Abstract
BACKGROUND The Glissonean approach has been widely validated for both open and minimally invasive anatomic liver resection (MIALR). However, the possible advantages compared to the conventional hilar approach are still under debate. The aim of this systematic review was to evaluate the application of the Glissonean approach in MIALR. METHODS A systematic review of the literature was conducted on PubMed and Ichushi databases. Articles written in English or Japanese were included. From 2,390 English manuscripts evaluated by title and abstract, 43 were included. Additionally, 23 out of 463 Japanese manuscripts were selected. Duplicates were removed, including the most recent manuscript. RESULTS The Glissonean approach is reported for both major and minor MIALR. The 1st, 2nd and 3rd order divisions of both right and left portal pedicles can be reached following defined anatomical landmarks. Compared to the conventional hilar approach, the Glissonean approach is associated with shorter operative time, lower blood loss, and better peri-operative outcomes. CONCLUSIONS Glissonean approach is safe and feasible for MIALR with several reported advantages compared to the conventional hilar approach. Clear knowledge of Laennec's capsule anatomy is necessary and serves as a guide for the dissection. However, the best surgical approach to be performed depends on surgeon experience and patients' characteristics. Standardization of the Glissonean approach for MIALR is important.
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- 2021
79. Resectional surgery in gallbladder cancer with jaundice—how to improve the outcome?
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Yutaro Matsunaga, Toru Furukawa, Wataru Izumo, Takehiro Ota, Masakazu Yamamoto, Yasuto Sato, Takehisa Yazawa, Erika Nagano, Shuichirou Uemura, Rahul K. Chaudhary, and Ryota Higuchi
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medicine.medical_specialty ,business.industry ,Hazard ratio ,030230 surgery ,Jaundice ,Vascular surgery ,medicine.disease ,Surgery ,03 medical and health sciences ,0302 clinical medicine ,Cardiothoracic surgery ,030220 oncology & carcinogenesis ,medicine ,Radical surgery ,Gallbladder cancer ,medicine.symptom ,business ,Survival rate ,Abdominal surgery - Abstract
To evaluate the surgical outcomes of patients with gallbladder cancer (GBC) with jaundice due to as-yet unelucidated prognostic factors. A total of 348 GBC patients underwent resection at our institute between 1985 and 2016. Of these, 67 had jaundice (serum total bilirubin ≥ 2 mg/dL). Preoperative biliary drainage was performed, with portal vein embolization as required. All patients underwent radical surgery. We retrospectively evaluated the outcomes, performed multivariate analysis for overall survival, and compared our findings to those reported in the literature. The 5-year survival rate of M0 (no distant metastasis) GBC patients with jaundice, who underwent resectional surgery, was 21.9%, versus 68.3% in those without jaundice (p < 0.05). Since 2000, surgical mortality in GBC patients with jaundice has decreased from 12 to 6.8%. Patients with jaundice had more advanced disease and underwent major hepatectomies and vascular resections; however, preoperative jaundice alone was not a prognostic factor. Multivariate analysis of jaundiced patients revealed that percutaneous biliary drainage (PTBD) (vis-a-vis endoscopic drainage [EBD], hazard ratio [HR] 2.82), postoperative morbidity (Clavien–Dindo classification ≥ 3, HR 2.31), and distant metastasis (HR 1.85) were predictors of poor long-term survival. The 5-year survival and peritoneal recurrence rates in M0 patients with jaundice were 16% and 44%, respectively, for patients with PTBD and 39% (p < 0.05) and 13% (p = 0.07) for those with EBD. M0 GBC patients with jaundice should undergo surgery if R0 resection is possible. Preoperative EBD may be superior to PTBD in M0 GBC patients with jaundice, although further studies are needed.
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- 2021
80. Landmarks and techniques to perform minimally invasive liver surgery: A systematic review with a focus on hepatic outflow
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Rawisak Chanwat, Yoshihiro Miyasaka, Ho-Seong Han, Goro Honda, Osamu Itano, Satoshi Ogiso, Yukio Iwashita, Itaru Endo, Ruben Ciria, Giammauro Berardi, Yoshihiro Sakamoto, Felipe Alconchel, Kuo-Hsin Chen, Atsushi Sugioka, Mohammed Abu Hilal, Kiyoshi Hasegawa, Fernando Rotellar, Kazuteru Monden, Santiago López‐Ben, Alain Garcia Vazquez, David A. Geller, Etsuro Hatano, Tomoharu Yoshizumi, Federico Tomassini, Takeshi Aoki, Yutaro Kato, Hironori Kaneko, Shunichi Ariizumi, Takeshi Urade, Hitoe Nishino, Yasuhisa Mori, Rong Liu, Masakazu Yamamoto, Manuel Durán, Chikara Shirata, Minoru Tanabe, Keiichi Akahoshi, Horacio J. Asbun, Ji Hoon Kim, Taiga Wakabayashi, Go Wakabayashi, David Fuks, Yuta Abe, Daniel Cherqui, Yajin Chen, Nicolas Golse, Albert C. Y. Chan, Mamoru Morimoto, Andrea Benedetti Cacciaguerra, Naoto Gotohda, Akihiko Tsuchida, and Tan To Cheung
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Hepatic vein injury ,Liver surgery ,medicine.medical_specialty ,Hepatology ,Quality assessment ,business.industry ,MEDLINE ,Hepatic Veins ,030230 surgery ,Resection ,03 medical and health sciences ,0302 clinical medicine ,Bleeding control ,Liver ,030220 oncology & carcinogenesis ,Hepatic veins ,Hepatectomy ,Humans ,Minimally Invasive Surgical Procedures ,Medicine ,Surgery ,Medical physics ,business - Abstract
Purpose In this systematic review, we aimed to clarify the useful anatomic structures and assess available surgical techniques and strategies required to safely perform minimally invasive anatomic liver resection (MIALR), with a particular focus on the hepatic veins (HVs). Methods A systematic review was conducted using MEDLINE/PubMed for English articles and Ichushi databases for Japanese articles through September 2020. The quality assessment of the articles was performed in accordance with the Scottish Intercollegiate Guidelines Network (SIGN). Results A total of 3,372 studies were obtained, and 59 were selected and reviewed. Due to the limited number of published comparative studies and case series, the degree of evidence from our review was low. Thirty-two articles examined the anatomic landmarks and crucial structures for approaching HVs. Regarding the direction of HV exposure, 32 articles focused on the techniques and advantages of exposing HVs from either the root or the periphery. Ten articles focused on the techniques to perform a segmentectomy 8 in particularly difficult cases of MIALR. In seven articles, bleeding control from HVs was also discussed. Conclusions This review may help experts reach a consensus regarding the best approach to the management of hepatic veins during MIALR.
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- 2021
81. Landmarks to identify segmental borders of the liver: A review prepared for PAM‐HBP expert consensus meeting 2021
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Taiga, Wakabayashi, Andrea, Benedetti Cacciaguerra, Ruben, Ciria, Shunichi, Ariizumi, Manuel, Durán, Nicolas, Golse, Satoshi, Ogiso, Yuta, Abe, Takeshi, Aoki, Etsuro, Hatano, Osamu, Itano, Yoshihiro, Sakamoto, Tomoharu, Yoshizumi, Masakazu, Yamamoto, Go, Wakabayashi, and Akihiko, Tsuchida
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medicine.medical_specialty ,Consensus ,Hepatology ,Standardization ,business.industry ,Liver Neoplasms ,MEDLINE ,Expert consensus ,Hepatic Veins ,030230 surgery ,Liver segmentation ,Resection ,03 medical and health sciences ,0302 clinical medicine ,Surgical anatomy ,030220 oncology & carcinogenesis ,Invasive surgery ,Hepatectomy ,Humans ,Medicine ,Surgery ,Medical physics ,business ,English articles - Abstract
Background In preparation for the upcoming consensus meeting in Tokyo in 2021, this systematic review aimed to analyze the current available evidence regarding surgical anatomy of the liver, focusing on useful landmarks, strategies and technical tools to perform precise anatomic liver resection (ALR). Methods A systematic review was conducted on MEDLINE/PubMed for English articles and on Ichushi database for Japanese articles until September 2020. The quality assessment of the articles was performed in accordance with the Scottish Intercollegiate Guidelines Network (SIGN). Results A total of 3169 manuscripts were obtained, 1993 in English and 1176 in Japanese literature. Subsequently, 63 English and 20 Japanese articles were selected and reviewed. The quality assessment of comparative series and case series was revealed to be usually low; only six articles were qualified as high quality. Forty-two articles focused on analyzing intersegmental/sectional planes and their relationship with specific hepatic landmark veins. In 12 articles, the authors aimed to investigate liver surface anatomic structures, while 36 articles aimed to study technological tools and contrast agents for surgical segmentation during ALR. Although Couinaud's classification has remained the cornerstone in daily diagnostic/surgical practices, it does not always portray the realistic liver segmentation and there has been no standardization on which a single strategy should be followed to perform precise ALR. Conclusions A global consensus should be pursued in order to establish clear guidelines and proper recommendations to perform ALR in the era of minimally invasive surgery.
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- 2021
82. Long-term outcomes of regenerative treatment by endoscopic oral mucosal epithelial cell sheet transplantation for the prevention of esophageal stricture after endoscopic resection
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Takeshi Ohki, Masaho Ota, Ryo Takagi, Teruo Okano, and Masakazu Yamamoto
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- 2023
83. Assessment of Preoperative Clinicophysiologic Findings as Risk Factors for Postoperative Pancreatic Fistula After Pancreaticoduodenectomy
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Naoki Orimoto, Masakazu Yamamoto, Kiyotaka Nishida, Shuji Suzuki, Mitsugi Shimoda, Wataru Izumo, Jiro Shimazaki, Masahiro Shiihara, and Yukio Oshiro
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medicine.medical_specialty ,business.industry ,Pancreatic fistula ,medicine.medical_treatment ,Medicine ,Surgery ,business ,medicine.disease ,Pancreaticoduodenectomy - Abstract
Objective Postoperative pancreatic fistula (POPF) is one of the severe complications that develop after pancreaticoduodenectomy (PD). This study aimed to assess the utility of preoperative clinicophysiologic findings as risk factors for POPF after PD. Summary of Background Data We enrolled 350 patients who underwent PD between 2007 and 2012 at Tokyo Women's Medical University. Methods In total, 350 patients who underwent PD between 2007 and 2012 were examined retrospectively. All patients were classified into 2 groups as follows: group A (no fistula/biochemical leak group, 289 patients) and group B (grade B/C of POPF group 61 patients). Variables, including operative characteristics, length of stay in hospital, morbidity, mortality, and data regarding preoperative clinicophysiologic parameters, were collected and analyzed as predictors of POPF for univariate and multivariate analyses. Results There were 213 male and 137 female patients. The mean age was 65.4 years (range, 21–87 years). Univariate analysis showed that sex (P = 0.047), amylase level (P = 0.032), prognostic nutritional index (PNI; P = 0.001), and C-reactive protein/albumin ratio (P = 0.005) were independent risk factors for POPF. In contrast, multivariate analysis showed that sex (P = 0.045) and PNI (P = 0.012) were independent risk factors for POPF. Conclusions Our results show that PNI (≤48.64 U/mL) and male sex were risk factors for POPF after PD, and especially, PNI can be suggested as an effective biomarker for POPF.
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- 2021
84. Association of day of the week with mortality after elective right hemicolectomy for colon cancer: Case analysis from the National Clinical Database
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Masakazu Yamamoto, Kazuhiro Hanazaki, Hiroshi Hasegawa, Nao Ichihara, Hiroaki Miyata, Hideki Endo, Hiromichi Maeda, Kinji Kamiya, Kazuhiro Yoshida, Yasuyuki Seto, Yoshihiro Kakeji, Sunao Uemura, Yuko Kitagawa, and Hiroki Yamaue
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medicine.medical_specialty ,RD1-811 ,Colorectal cancer ,Names of the days of the week ,medicine.medical_treatment ,RC799-869 ,elective surgical procedures ,Logistic regression ,Internal medicine ,medicine ,Clinical endpoint ,Colectomy ,hospital mortality ,business.industry ,Gastroenterology ,colonic neoplasms ,Original Articles ,Odds ratio ,Diseases of the digestive system. Gastroenterology ,colectomy ,medicine.disease ,Confidence interval ,treatment outcome ,Original Article ,Surgery ,business ,Elective Surgical Procedure - Abstract
Aim We aimed to investigate whether later weekdays are related to worse short‐term outcomes after elective right hemicolectomy for colon cancer. Methods We retrospectively analyzed adult patients who underwent elective right hemicolectomy for colon cancer between 2012 and 2017. Records lacking details about surgical mortality were excluded, and multiple imputation was performed for other missing data (variables). The primary endpoint was surgical mortality, defined as the sum of 30‐day mortality and in‐hospital deaths within 90 days postoperatively. Using 22 clinical variables, hierarchal logistic regression modeling with clustering of patients from the same institutes was performed. Results Of the 112 658 patients undergoing elective right hemicolectomy for colon cancer, the 30‐day mortality and surgical mortality were 0.6% and 1.1%, respectively. Surgery on Friday was less frequent, accounting for 17.1% of all cases. The occurrence of severe postoperative complications, anastomotic leakage, or unadjusted odds ratio for surgical mortality did not show significant differences between weekdays. A hierarchal logistic regression model identified 19 independent factors for surgical mortality. Adjusted odds ratios for surgical mortality were 1.01 (95% confidence interval: 0.83‐1.22, P = .915), 0.86 (95% confidence interval: 0.71‐1.05, P = .144), 0.86 (95% confidence interval: 0.71‐1.05, P = .408), and 0.83 (95% confidence interval: 0.68‐1.03, P = .176) for Tuesday, Wednesday, Thursday, and Friday, respectively, showing no significant differences. Conclusion This study did not identify an evident difference in surgical mortality between weekdays; a safe elective right hemicolectomy for colon cancer is being offered throughout the week in Japan., Weekday effect on mortality.
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- 2021
85. Narrowing of the remnant portal vein diameter and decreased portal vein angle are risk factors for portal vein thrombosis after perihilar cholangiocarcinoma surgery
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Yutaro Matsunaga, Yasuto Sato, Takehisa Yazawa, Ryota Higuchi, Shuichiro Uemura, Wataru Izumo, Hiroto Egawa, Manh Thau Cao, Satoru Morita, Masakazu Yamamoto, and Toru Furukawa
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medicine.medical_specialty ,medicine.medical_treatment ,Cholangiocarcinoma ,03 medical and health sciences ,0302 clinical medicine ,Risk Factors ,medicine ,Hepatectomy ,Humans ,Retrospective Studies ,Venous Thrombosis ,Portal Vein ,business.industry ,Vascular surgery ,medicine.disease ,Surgery ,Cardiac surgery ,Portal vein thrombosis ,Venous thrombosis ,Bile Ducts, Intrahepatic ,medicine.anatomical_structure ,Bile Duct Neoplasms ,Cardiothoracic surgery ,030220 oncology & carcinogenesis ,030211 gastroenterology & hepatology ,business ,Klatskin Tumor ,Abdominal surgery ,Artery - Abstract
To evaluate the incidence, risk factors, management options, and outcomes of portal vein thrombosis following major hepatectomy for perihilar cholangiocarcinoma.A total of 177 perihilar cholangiocarcinoma patients who (1) underwent major hepatectomy and (2) underwent investigating the portal vein morphology, which was measured by rotating the reconstructed three-dimensional images after facilitating bone removal using Aquarius iNtuition workstation between 2002 and 2018, were included. Risk factors were evaluated using the Kaplan-Meier method and Cox proportional hazard models.Six patients developed portal vein thrombosis (3.4%) within a median time of 6.5 (range 0-22) days. Portal vein and hepatic artery resection were performed in 30% and 6% patients, respectively. A significant difference in the probability of the occurrence of portal vein thrombosis (PV) within 30 days was found among patients with portal vein resection, a postoperative portal vein angle100°, remnant portal vein diameter5.77 mm, main portal vein diameter13.4 mm, and blood loss (log-rank test, p = 0.003, p = 0.06, p0.0001, p = 0.01, and p = 0.03, respectively). Decreasing the portal vein angle and narrowing of the remnant PV diameter remained significant predictors on multivariate analysis (p = 0.027 and 0.002, respectively). Reoperation with thrombectomy was performed in four patients, and the other two patients were successfully treated with anticoagulants. All six patients subsequently recovered and were discharged between 25 and 70 days postoperatively.Narrowing of the remnant portal vein diameter and a decreased portal vein angle after major hepatectomy for perihilar cholangiocarcinoma are significant independent risk factors for postoperative portal vein thrombosis.
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- 2021
86. Case report of papillary carcinoma from thyroglossal cyst
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Ayaka Mori, Fujinobu Tanaka, Haruo Yoshida, Masakazu Yamamoto, Masahiro Ito, and Shiro Miura
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- 2021
87. Clinical practice guidelines for the management of liver metastases from extrahepatic primary cancers 2021
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H. Takeda, Tomohiko Ukai, Masakazu Yamamoto, Makoto Ueno, Steven M. Strasberg, René Adam, Mariano E Giménez, Takuro Mizukami, Naohiro Okano, Palepu Jagannath, Ho-Seong Han, Katsunori Sakamoto, Masato Ozaka, Takayuki Ueno, Susumu Hijioka, Koji Asai, Yoo Seok Yoon, Keita Wada, Keiji Sano, Toru Beppu, Satoru Shikata, Takako Eguchi Nakajima, Tsutomu Tabata, Shingo Yamashita, Do Youn Oh, Yoichi Naito, Tadahiro Takada, Taizo Hibi, Junji Furuse, Masayuki Ohtsuka, Koichi Hayano, Tsann Long Hwang, Hee-Jung Wang, Masahiro Yoshida, Teijiro Hirashita, Nozomu Sakai, Shao Ciao Luo, Hisato Kawakami, Yukio Iwashita, Ryusei Matsuyama, Michael G. Sarr, Olivier Scatton, and Yasuhisa Mori
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medicine.medical_specialty ,medicine.medical_treatment ,Population ,030230 surgery ,Malignancy ,Systemic therapy ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Hepatectomy ,Humans ,education ,Grading (tumors) ,education.field_of_study ,Hepatology ,business.industry ,General surgery ,Standard treatment ,Liver Neoplasms ,medicine.disease ,Clinical trial ,Systematic review ,030220 oncology & carcinogenesis ,Surgery ,business - Abstract
Background Hepatectomy is standard treatment for colorectal liver metastases; however, it is unclear whether liver metastases from other primary cancers should be resected or not. The Japanese Society of Hepato-Biliary-Pancreatic Surgery therefore created clinical practice guidelines for the management of metastatic liver tumors. Methods Eight primary diseases were selected based on the number of hepatectomies performed for each malignancy per year. Clinical questions were structured in the population, intervention, comparison, and outcomes (PICO) format. Systematic reviews were performed, and the strength of recommendations and the level of quality of evidence for each clinical question were discussed and determined. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess evidence and make recommendations. Results The eight primary sites were grouped into five categories based on suggested indications for hepatectomy and consensus of the guidelines committee. Fourteen clinical questions were devised, covering five topics: (1) diagnosis, (2) operative treatment, (3) ablation therapy, (4) the eight primary diseases, and (5) systemic therapies. The grade of recommendation was strong for one clinical question and weak for the other 13 clinical questions. The quality of the evidence was moderate for two questions, low for 10, and very low for two. A flowchart was made to summarize the outcomes of the guidelines for the indications of hepatectomy and systemic therapy. Conclusions These guidelines were developed to provide useful information based on evidence in the published literature for the clinical management of liver metastases, and they could be helpful for conducting future clinical trials to provide higher-quality evidence.
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- 2020
88. Evaluation of preoperative prognostic factors in patients with resectable invasive intraductal papillary mucinous carcinoma
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Toru Furukawa, Takehisa Yazawa, Masahiro Shiihara, Ryota Higuchi, Shuichiro Uemura, Masakazu Yamamoto, and Wataru Izumo
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Male ,medicine.medical_specialty ,Multivariate analysis ,CA-19-9 Antigen ,Kaplan-Meier Estimate ,030230 surgery ,Risk Assessment ,Gastroenterology ,Disease-Free Survival ,03 medical and health sciences ,Pancreatectomy ,0302 clinical medicine ,Predictive Value of Tests ,Risk Factors ,Internal medicine ,Antineoplastic Combined Chemotherapy Protocols ,Humans ,Medicine ,Mucinous carcinoma ,Neoplasm Invasiveness ,In patient ,Risk factor ,Aged ,Retrospective Studies ,Aged, 80 and over ,Tumor size ,business.industry ,Standard treatment ,Hazard ratio ,Middle Aged ,Prognosis ,medicine.disease ,Adenocarcinoma, Mucinous ,Pancreatic Neoplasms ,Survival Rate ,Chemotherapy, Adjuvant ,Lymphatic Metastasis ,030220 oncology & carcinogenesis ,Preoperative Period ,Tubular Adenocarcinoma ,Female ,Surgery ,Neoplasm Recurrence, Local ,business ,Carcinoma, Pancreatic Ductal ,Follow-Up Studies - Abstract
Background Upfront surgery is the standard treatment for resectable invasive intraductal papillary mucinous carcinoma; however, recurrence is common. Therefore, we investigated the recurrence, surgical outcome, and preoperative prognostic factors for recurrence in patients with resectable invasive intraductal papillary mucinous carcinoma. Methods We analyzed 111 patients who underwent upfront surgery for resectable invasive intraductal papillary mucinous carcinoma between 2000 and 2017 and evaluated the relationship among clinicopathologic factors, recurrence, and outcomes. Results The 5-year recurrence-free survival and disease-specific survival rates were 61% and 74%, respectively. The median time to recurrence was 1.1 years. In multivariate analysis, carbohydrate antigen 19-9 ≥83 U/mL (hazard ratio: 2.8 and 3.1), tumor size ≥2.2 cm (hazard ratio: 3.5 and 4.7), and pathologic tubular adenocarcinoma grade 2 (hazard ratio: 3.1 and 5.2) were risk factors for a shorter recurrence-free survival and disease-specific survival, respectively. Lymph node metastasis (hazard ratio: 3.9) was also a risk factor for a shorter disease-specific survival. When examining outcomes according to preoperatively measurable factors (carbohydrate antigen 19-9 ≥83 U/mL and tumor size ≥2.2 cm), the 5-year recurrence rates in patients with none (n = 47), 1 (n = 46), and both (n = 18) risk factors were 17%, 48%, and 78%, respectively. Five-year disease-specific survival rates in patients with none, 1, and both preoperative risk factors were 95%, 69%, and 31%, respectively. Conclusion Carbohydrate antigen 19-9 ≥83 U/mL and tumor size ≥2.2 cm were independent preoperative risk factors for poor outcomes in patients with resectable invasive intraductal papillary mucinous carcinoma.
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- 2020
89. Author response for 'Over‐expression of wild‐type <scp> ACVR1 </scp> in fibrodysplasia ossificans progressiva mice rescues perinatal lethality and inhibits heterotopic ossification'
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null Masakazu Yamamoto, null Sean J. Stoessel, null Shoko Yamamoto, and null David J. Goldhamer
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- 2022
90. Asymptotic Expansion of Solutions to the Dissipative Equation with Fractional Laplacian.
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Masakazu Yamamoto
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- 2012
- Full Text
- View/download PDF
91. Environmental Support Method for Mobile Robots Using Visual Marks with Memory Storage.
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Jun Ota 0001, Masakazu Yamamoto, Kazuo Ikeda, Yasumichi Aiyama, and Tamio Arai
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- 1999
- Full Text
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92. Asymptotic stability of stationary solutions to the drift-diffusion model with the fractional dissipation
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Yuusuke Sugiyama and Masakazu Yamamoto
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010101 applied mathematics ,Mathematics (miscellaneous) ,Exponential growth ,Exponential stability ,010102 general mathematics ,Mathematical analysis ,Uniqueness ,0101 mathematics ,Dissipation ,Space (mathematics) ,Stationary solution ,01 natural sciences ,Mathematics - Abstract
We study the drift-diffusion equation with fractional dissipation $$(-\varDelta )^{\theta /2}$$ arising from a model of semiconductors. First, we prove the existence and uniqueness of the small solution to the corresponding stationary problem in the whole space. Moreover, it is proved that the unique solution of non-stationary problem exists globally in time and decays exponentially, if initial data are suitably close to the stationary solution and the stationary solution is sufficiently small.
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- 2020
93. A case of hemorrhage of hepatocellular carcinoma resembling a hepatic cyst arising from non-cirrhotic steatohepatitis
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Satomi Saito, Takaomi Sagawa, Katsutoshi Tokushige, Akiko Omori, Masakazu Yamamoto, Yoshihito Kotera, Kyoko Shimizu, Masayuki Nakano, Tomomi Kogiso, Makiko Taniai, and Sho Yatsuji
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Pathology ,medicine.medical_specialty ,Carcinoma, Hepatocellular ,Hemorrhage ,Malignancy ,Lesion ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,Cyst ,Aged ,medicine.diagnostic_test ,Cysts ,business.industry ,Liver Neoplasms ,Gastroenterology ,Magnetic resonance imaging ,General Medicine ,medicine.disease ,Fatty Liver ,030220 oncology & carcinogenesis ,Hepatocellular carcinoma ,Reticular connective tissue ,Female ,030211 gastroenterology & hepatology ,Hepatic Cyst ,Steatohepatitis ,medicine.symptom ,business - Abstract
A 70-year-old female was found to have multiple hepatic cysts at her annual checkup. In the posterior segment of the right lobe of the liver, an 81 × 67 mm circular cystic lesion was detected by contrast-enhanced computed tomography (CT). Magnetic resonance imaging (MRI) of the cyst revealed a solid component. The cyst had a capsule-like structure and non-uniform fluid accumulation suggested bleeding. Since the lesion was enlarged and malignancy could not be ruled out, it was surgically resected. Histopathologically, reticular fibers of the liver were seen in necrotic tissue and the lesion was diagnosed as a bleeding hepatocellular carcinoma (HCC). The non-cancerous liver tissue showed non-cirrhotic steatohepatitis. This was an unusual presentation of HCC.
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- 2020
94. Successful treatment of recurrent volvulus in the afferent limb of the pouch following proctocolectomy for ulcerative colitis: a case report
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Kimitaka Tani, Shinpei Ogawa, Takeshi Ohki, Hisako Aihara, Ryousuke Nakagawa, Yuji Inoue, Michio Itabashi, Masakazu Yamamoto, Kurodo Koshino, and Yoshiko Bamba
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Laparoscopic surgery ,medicine.medical_specialty ,Abdominal pain ,medicine.medical_treatment ,lcsh:Surgery ,Case Report ,Anastomosis ,Volvulus ,03 medical and health sciences ,0302 clinical medicine ,parasitic diseases ,Medicine ,Afferent limb volvulus ,business.industry ,Proctocolectomy ,Pouchpexy ,Postoperative complication ,lcsh:RD1-811 ,medicine.disease ,digestive system diseases ,Surgery ,Bowel obstruction ,Pouch volvulus ,Ulcerative colitis ,030220 oncology & carcinogenesis ,030211 gastroenterology & hepatology ,Pouch ,medicine.symptom ,business - Abstract
Background Pouch volvulus after proctocolectomy for ulcerative colitis is a very rare postoperative complication. The common site of pouch volvulus has been reported to be the ileal pouch–anal anastomosis and the middle part of the pouch, but no reports on pouch volvulus in the afferent limb of the pouch have been observed. Here, we report the case of a patient with afferent limb volvulus who underwent afferent limbpexy, but required reoperation 7 months later. Case presentation A 38-year-old man with refractory ulcerative colitis had undergone open proctocolectomy 10 years ago at another hospital. He had been aware of lower abdominal pain and bowel movement difficulty for 2 years. After repeated bowel obstruction, he was referred to our hospital for surgery. Based on the radiographic findings, we diagnosed a pouch volvulus and performed an operation. Laparoscopically, counterclockwise rotation of the afferent limb of the pouch was recognized. Moreover, the ileal mesentery was adhered and fixed to the presacral space 20 cm from the oral side of the pouch. The antimesenteric side of the afferent limb was fixed using interrupted stiches on the left peritoneal wall of the pelvis. He was discharged uneventfully 18 days after surgery, and defecation improved immediately. However, he was readmitted 7 months after surgery with the same abdominal pain and defecation difficulty. A similar finding was found and diagnosed as recurrent volvulus. Therefore, we performed a laparoscopic surgery. The same volvulus as in the previous surgery was confirmed. The site fixed during the previous surgery showed scars, but the afferent limb was free. The dilated ileum that contained the volvulus was excised only on the oral side of the pouch and an intraluminal anastomosis was performed on the anterior wall of the pouch. He had a good postoperative course and was discharged. Conclusion Proper diagnosis of volvulus based on the characteristic imaging findings is important. In principle, bilateral row fixation of the rotated ileum is the basic procedure for volvulus. However, fixation with this technique is sometimes difficult. Therefore, this procedure is one of the useful options for the fixation of difficult or recurrent cases.
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- 2020
95. Different response rates to chemotherapy between Japanese and German esophageal squamous cell carcinoma: patients may be influenced by ERCC1 or ABCB1
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Hakan Alakus, Masakazu Yamamoto, Kosuke Narumiya, Ute Warnecke-Eberz, Ralf Metzger, Uta Drebber, Elfriede Bollschweiler, and Arnulf H. Hölscher
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Oncology ,Cisplatin ,Cancer Research ,medicine.medical_specialty ,Chemotherapy ,business.industry ,medicine.medical_treatment ,Single-nucleotide polymorphism ,General Medicine ,Esophageal squamous cell carcinoma ,language.human_language ,German ,Internal medicine ,Genotype ,medicine ,language ,Biomarker (medicine) ,ERCC1 ,business ,medicine.drug - Abstract
Aim: To find out differences in biomarkers between Japanese and German patients responsible for response after neoadjuvant radio/chemotherapy and survival for esophageal squamous cell carcinoma. Materials & methods: A total of 60 patients from Japan and 127 patients from Germany with esophageal squamous cell carcinoma were analyzed according to three SNPs by real-time PCR. Results: The distribution of the genotypes of ERCC1 rs16115 and ABCB1 C3435T rs1045642 was significantly different between both patients’ groups. Japanese patients had significantly less good response to 5-fluorouracil/cisplatin chemotherapy. The influence of the three SNPs on response varied between patients from Japan and Germany. Conclusion: Different expressions of ERCC1 and ABCB1 SNPs of Japanese patients compared with the German patients partially explain the different response.
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- 2020
96. Whole-exome Sequencing Reveals New Potential Susceptibility Genes for Japanese Familial Pancreatic Cancer
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Ryota Higuchi, Toru Furukawa, Junji Furuse, Shinichi Yachida, Emi Kubo, Yasushi Totoki, Akihiro Ohmoto, Erina Takai, Tatsuhiro Shibata, Chigusa Morizane, Hiromi Nakamura, Masakazu Yamamoto, Hideaki Takahashi, Kyoko Shimizu, and Suenori Chiku
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Candidate gene ,Copy number analysis ,medicine.disease_cause ,Germline ,Proto-Oncogene Proteins p21(ras) ,Loss of heterozygosity ,03 medical and health sciences ,0302 clinical medicine ,Japan ,Exome Sequencing ,medicine ,Humans ,Genetic Predisposition to Disease ,Germ-Line Mutation ,Exome sequencing ,Genetic testing ,Genetics ,medicine.diagnostic_test ,business.industry ,Carcinoma ,Pancreatic Neoplasms ,030220 oncology & carcinogenesis ,030211 gastroenterology & hepatology ,Surgery ,KRAS ,Carcinogenesis ,business - Abstract
Objective The primary objective of this study was to identify novel genes that predispose people in the Japanese population to FPC. Summary of background data Familial history of pancreatic cancer is an important risk factor but, to date, few genes predisposing individuals to increased risk of developing FPC have been identified. Methods We performed whole-exome sequencing of germline DNA from 81 Japanese FPC patients. We also investigated somatic gene alterations in 21 matched tumor tissues through whole-exome sequencing and copy number analysis. Results Our germline variants identified previously known FPC susceptibility genes such as ATM and BRCA2, and several novel tumor suppressor genes with potentially deleterious variants for FPC. Interestingly, somatic whole-exome analysis demonstrated that most tumor samples with suspicious loss of heterozygosity of candidate genes were KRAS wild-types, implying that these cases may not have required KRAS activation as a driver event for carcinogenesis. Conclusions Our findings indicate that FPC patients harbor potentially deleterious causative germline variants in tumor suppressor genes, which are known to acquire somatic mutations in pancreatic cancer, and that somatic loss of heterozygosity of some FPC susceptibility genes may contribute to the development of FPC in the absence of somatic KRAS-activating mutation. Genetic testing for a wider variety of FPC-predisposition genes could provide better screening approach for high-risk groups of pancreatic cancer.
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- 2020
97. Clinical and anthropometric characteristics of non‐obese non‐alcoholic fatty liver disease subjects in Japan
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Natsumi Oshida, Taeho Kim, Hideo Suzuki, Sechang Oh, Takashi Shida, Shunichi Ariizumi, Junichi Shoda, Kosuke Okada, Tomonori Isobe, Masakazu Yamamoto, Takahisa Watahiki, and Yoshikazu Okamoto
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medicine.medical_specialty ,Hepatology ,business.industry ,Leptin ,Fatty liver ,nutritional and metabolic diseases ,medicine.disease ,digestive system ,Gastroenterology ,Obesity ,digestive system diseases ,Muscle atrophy ,Impaired glucose tolerance ,03 medical and health sciences ,0302 clinical medicine ,Infectious Diseases ,Insulin resistance ,030220 oncology & carcinogenesis ,Internal medicine ,medicine ,030211 gastroenterology & hepatology ,Steatosis ,medicine.symptom ,business ,Body mass index - Abstract
AIM The underlying mechanism of non-obese non-alcoholic fatty liver disease (NAFLD) has not been fully elucidated. We classified patients with NAFLD by sex and body mass index and compared their clinical features to clarify the background pathophysiology of non-obese NAFLD. METHODS A total of 404 patients with NAFLD were divided according to their body mass index (
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- 2020
98. Prognostic Factors for Surgically Resected Intraductal Papillary Neoplasm of the Bile Duct: A Retrospective Cohort Study
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Masakazu Yamamoto, Takehiro Ota, Wataru Izumo, Ryota Higuchi, Shuichiro Uemura, Takehisa Yazawa, Masahiro Shiihara, Yutaro Matsunaga, and Toru Furukawa
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medicine.medical_specialty ,Multivariate analysis ,030230 surgery ,Gastroenterology ,03 medical and health sciences ,0302 clinical medicine ,Surgical oncology ,Internal medicine ,medicine ,Humans ,Retrospective Studies ,business.industry ,Bile duct ,Carcinoma in situ ,Hazard ratio ,Cancer ,Retrospective cohort study ,Prognosis ,medicine.disease ,medicine.anatomical_structure ,Bile Duct Neoplasms ,Oncology ,Dysplasia ,030220 oncology & carcinogenesis ,Surgery ,Bile Ducts ,Neoplasm Recurrence, Local ,business - Abstract
To date, postoperative prognostic factors for intraductal papillary neoplasm of the bile duct (IPNB) have not been well-established. This study aimed to examine the histopathologic features and postoperative prognosis of the two IPNB subclassifications, as well as factors affecting prognosis, based on the authors’ experience at a single institution. The study enrolled 83 patients who underwent surgical resection for pathologically diagnosed IPNB at the authors’ institution. The clinicopathologic features and postoperative outcomes for these patients were examined. The study also investigated postoperative prognostic factors for IPNB using uni- and multivariate analyses. More than half of the tumors (64%) diagnosed as IPNB were early-stage cancer (UICC Tis or T1). However, none were diagnosed as benign. The multivariate analysis showed that lymph node metastasis (hazard ratio [HR], 5.78; p = 0.002) and bile duct margin status with carcinoma in situ (D-CIS; HR, 5.10; p = 0.002) were independent prognostic factors, whereas MUC6 expression showed only a marginal influence on prediction of prognosis (HR, 0.32; p = 0.07). The tumor recurrence rate and the proportion of locoregional recurrence were significantly greater among the patients with D-CIS than among those with negative bile duct margins, including those patients with low-grade dysplasia. The patients with D-CIS showed a significantly poorer prognosis than those with negative bile duct margins (5-year survival, 38% versus 87%; p = 0.0002). Evaluation of resected IPNBs showed cancer in all cases. Avoiding positive biliary stumps during surgery, including resection of carcinoma in situ, would improve the prognosis for patients with IPNB.
- Published
- 2020
99. Impact of comorbidity and relative dose intensity on outcomes in diffuse large B-cell lymphoma patients treated with R-CHOP
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Ikuko Suzuki, Katsushi Tajima, Shuhei Okuyama, Hiroaki Kumagai, Masakazu Yamamoto, Eijiro Omoto, Kouji Saitou, Riko Tsumanuma, and Shinji Satoh
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Adult ,Male ,0301 basic medicine ,Cancer Research ,medicine.medical_specialty ,animal structures ,Multivariate analysis ,Comorbidity ,Gastroenterology ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Antineoplastic Combined Chemotherapy Protocols ,medicine ,Humans ,Cyclophosphamide ,Aged ,Aged, 80 and over ,Hematology ,Poor risk ,business.industry ,General Medicine ,Middle Aged ,medicine.disease ,Dose intensity ,Progression-Free Survival ,nervous system diseases ,Lymphoma ,Treatment Outcome ,030104 developmental biology ,Oncology ,Doxorubicin ,Vincristine ,030220 oncology & carcinogenesis ,Charlson comorbidity index ,Prednisone ,Female ,Lymphoma, Large B-Cell, Diffuse ,Rituximab ,business ,Diffuse large B-cell lymphoma ,psychological phenomena and processes - Abstract
Comorbidity and relative dose intensity (RDI) have been associated with survival in diffuse large B-cell lymphoma (DLBCL) patients, but both relationships remain unaddressed in the same patients. A retrospective review of consecutive DLBCL patients treated from January 2010 to October 2018 was performed. Data for the clinical characteristics of the patients, including the Charlson Comorbidity Index (CCI) and RDI, on their outcomes were evaluated. A total of 211 patients with a median age of 72 years (range 19–90 years) were analyzed. CCI ≥ 2 was associated with poor event-free survival (EFS) and overall survival (OS). RDI
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- 2020
100. Comprehensive data of 3525 patients newly diagnosed with colorectal liver metastasis between 2013 and 2014: 2nd report of a nationwide survey in Japan
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Masaru Miyazaki, Hirotoshi Kobayashi, Goro Honda, Ken Tabuchi, Satoshi Morita, Michio Itabashi, Kiyoshi Hasegawa, Yoshihito Kotera, Keiichi Takahashi, Katsunori Sakamoto, Toru Beppu, Shin Kobayashi, Tatsuro Yamaguchi, Kenichi Sugihara, Yojiro Hashiguchi, Kensei Yamaguchi, Masakazu Yamamoto, Itaru Endo, and Kenjiro Kotake
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Adult ,Male ,medicine.medical_specialty ,Treatment outcome ,Newly diagnosed ,Nationwide survey ,Metastasis ,03 medical and health sciences ,0302 clinical medicine ,Japan ,Surveys and Questionnaires ,medicine ,Humans ,In patient ,Liver neoplasm ,Prospective Studies ,Aged ,Aged, 80 and over ,Hepatology ,business.industry ,General surgery ,Liver Neoplasms ,Cancer ,Middle Aged ,medicine.disease ,Surgery ,030220 oncology & carcinogenesis ,Female ,030211 gastroenterology & hepatology ,Colorectal Neoplasms ,Raw data ,business - Abstract
To collect large-scale data for further research to improve treatment outcomes in patients with colorectal liver metastasis (CRLM), the Joint Committee for Nationwide Survey on CRLM was established by the Japanese Society for Cancer of the Colon and Rectum and the Japanese society of Hepato-Biliary-Pancreatic Surgery. The joint committee was initiated to collect data since 2014 and has already reported data including the prognostic data of 3820 patients newly diagnosed with CRLM between 2005 and 2007.The data of patients newly diagnosed with CRLM after 2013 are continuously being registered prospectively, and herein, we report the data of the patients newly diagnosed with CRLM in 2013 and 2014.The data of 3839 patients newly diagnosed with CRLM in 2013 and 2014 were registered from 156 departments (75%) of 152 institutions among 209 departments (from 201 institutions) that agreed to participate in this database system at its initiation. Finally, 3525 patients were enrolled in this study after a quality management process conducted by the joint committee. We report the comprehensive data obtained from 3525 patients, including clinicopathological findings, treatment strategies, and implementation status of chemotherapy.The joint committee will provide these raw data while updating prognostic data to researchers who will conduct meaningful studies that meet the aim of the joint committee.
- Published
- 2020
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