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Abstract Background Postoperative pancreatic fistula (POPF) continues to be the most common complication after distal pancreatectomy (DP). Recent advancements in surgical techniques have established minimally invasive distal pancreatectomy (MIDP) as the standard treatment for various conditions, including pancreatic cancer. However, MIDP has not demonstrated a clear advantage over open DP in terms of POPF rates, indicating the need for additional strategies to prevent POPF in MIDP. This trial (WRAP study) aims to evaluate the efficacy of wrapping the pancreatic stump with polyglycolic acid (PGA) mesh and fibrin glue in preventing clinically relevant (CR-) POPF following MIDP. Methods This multicenter, randomized controlled trial will include patients scheduled for laparoscopic or robotic DP for tumors in the pancreatic body and/or tail. Eligible participants will be centrally randomized into either the control group (Group A) or the intervention group (Group B), where the pancreatic stump will be reinforced by PGA mesh and fibrin glue. In both groups, pancreatic transection will be performed using a bioabsorbable reinforcement-attached stapler. A total of 172 patients will be enrolled across 14 high-volume centers in Japan. The primary endpoint is the incidence of CR-POPF (International Study Group of Pancreatic Surgery grade B/C). Discussion The WRAP study will determine whether the reinforcement of the pancreatic stump with PGA mesh and fibrin glue, a technique whose utility has been previously debated, could become the best practice in the era of MIDP, thereby enhancing its safety. Trial registration This trial was registered with the Japan Registry of Clinical Trials on June 15, 2024 (jRCTs032240120).

Abstract Background Tumor-associated neutrophils (TANs) constitute an abundant component among tumor-infiltrating immune cells and have recently emerged as a critical player in pancreatic ductal adenocarcinoma (PDAC) progression. This study aimed to elucidate the pro-tumor mechanisms of TAN and identify a novel target for effective immunotherapy against PDAC. Methods Microarray and cytokine array analyses were performed to identify the mechanisms underlying the function of TANs. Human and mouse TANs were obtained from differentiated HL-60 cells and orthotopically transplanted PDAC tumors, respectively. The interactions of TANs with cancer and cytotoxic T-cells were evaluated through in vitro co-culture and in vivo orthotopic or subcutaneous models. Single-cell transcriptomes from patients with PDAC were analyzed to validate the cellular findings. Results Increased neutrophil infiltration in the tumor microenvironment was associated with poor survival in patients with PDAC. TANs secreted abundant amounts of chemokine ligand 5 (CCL5), subsequently enhancing cancer cell migration and invasion. TANs subpopulations negatively correlated with cytotoxic CD8+ T-cell infiltration in PDAC and promoted T-cell dysfunction. TANs upregulated the membranous expression of Nectin2, which contributed to CD8+ T-cell exhaustion. Blocking Nectin2 improved CD8+ T-cell function and suppressed tumor progression in the mouse model. Single-cell analysis of human PDAC revealed two immunosuppressive TANs phenotypes: Nectin2+ TANs and OLR1+ TANs. Endoplasmic reticulum stress regulated the protumor activities in TANs. Conclusions TANs enhance PDAC progression by secreting CCL5 and upregulating Nectin2. Targeting the immune checkpoint Nectin2 could represent a novel strategy to enhance immunotherapy efficacy in PDAC.

Abstract Background Pancreatic ductal adenocarcinoma tumors exhibit resistance to chemotherapy, targeted therapies, and even immunotherapy. Dendritic cells use glucose to support their effector functions and play a key role in anti-tumor immunity by promoting cytotoxic CD8+ T cell activity. However, the effects of glucose and lactate levels on dendritic cells in pancreatic ductal adenocarcinoma are unclear. In this study, we aimed to clarify how glucose and lactate can impact the dendritic cell antigen-presenting function and elucidate the relevant mechanisms. Methods Glycolytic activity and immune cell infiltration in pancreatic ductal adenocarcinoma were evaluated using patient-derived organoids and resected specimens. Cell lines with increased or decreased glycolysis were established from KPC mice. Flow cytometry and single-cell RNA sequencing were used to evaluate the impacts on the tumor microenvironment. The effects of glucose and lactate on the bone marrow-derived dendritic cell antigen-presenting function were detected by flow cytometry. Results The pancreatic ductal adenocarcinoma tumor microenvironment exhibited low glucose and high lactate concentrations from varying levels of glycolytic activity in cancer cells. In mouse transplantation models, tumors with increased glycolysis showed enhanced myeloid-derived suppressor cell infiltration and reduced dendritic cell and CD8+ T cell infiltration, whereas tumors with decreased glycolysis displayed the opposite trends. In three-dimensional co-culture, increased glycolysis in cancer cells suppressed the antigen-presenting function of bone marrow-derived dendritic cells. In addition, low-glucose and high-lactate media inhibited the antigen-presenting and mitochondrial functions of bone marrow-derived dendritic cells. Conclusions Our study demonstrates the impact of dynamic glycolytic reprogramming on the composition of immune cells in the tumor microenvironment of pancreatic ductal adenocarcinoma, especially on the antigen-presenting function of dendritic cells.

Abstract Background Distal pancreatectomy (DP) with lymph node (LN) dissection is the standard procedure for pancreatic ductal adenocarcinoma of the tail (Pt‐PDAC). However, the optimal surgery including extent of LN dissection is still being debated. The present study investigated the incidence and prognostic impact of LN metastasis on patients suffering from Pt‐PDAC. Patients and method This multicenter, retrospective study involved 163 patients who underwent DP for resectable Pt‐PDAC at 12 institutions between 2013 and 2017. The frequency of LN metastasis and the effect of LN dissection on Pt‐PDAC prognosis were investigated. Results There were high incidences of metastases to the LNs along the splenic artery in the patients with Pt‐PDAC (39%). The rate of metastases in the LNs along the common hepatic, left gastric, and celiac arteries were low, and the therapeutic index for these LNs was zero. In pancreatic tail cancer located more distally, there were no metastases to the LNs along the common hepatic artery. Multivariate analysis revealed that tumor size was the only independent factor related to recurrence‐free survival (HR = 2.01, 95% CI = 1.33–3.05, p = 0.001). The level of pancreas division and LN dissection along the common hepatic artery did not affect the site of tumor recurrence or recurrence‐free survival. Conclusions LN dissection along the hepatic artery for Pt‐PDAC has little significance. Distal pancreatic transection may be acceptable in terms of oncological safety, but further examination of short‐term outcomes and preservation of pancreatic function is required.

Abstract This study aimed to confirm urinary protein fragments in relation to the presence of pancreatic ductal adenocarcinoma (PDAC) via a C-terminal proteomics strategy using exploratory and validation cohorts. Urinary fragments were examined by iTRAQ-labelling of tryptic peptides and concentrations of C-terminal fragments were evaluated. Only the urinary CD276 fragment showed a fold change (FC) of > 1.5 with a significant difference of P

Abstract Background Although immune checkpoint blockade (ICB) therapy has proven to be extremely effective at managing certain cancers, its efficacy in treating pancreatic ductal adenocarcinoma (PDAC) has been limited. Therefore, enhancing the effect of ICB could improve the prognosis of PDAC. In this study, we focused on the histamine receptor H1 (HRH1) and investigated its impact on ICB therapy for PDAC. Methods We assessed HRH1 expression in pancreatic cancer cell (PCC) specimens from PDAC patients through public data analysis and immunohistochemical (IHC) staining. The impact of HRH1 in PCCs was evaluated using HRH1 antagonists and small hairpin RNA (shRNA). Techniques including Western blot, flow cytometry, quantitative reverse transcription polymerase chain reaction (RT-PCR), and microarray analyses were performed to identify the relationships between HRH1 and major histocompatibility complex class I (MHC-I) expression in cancer cells. We combined HRH1 antagonism or knockdown with anti-programmed death receptor 1 (αPD-1) therapy in orthotopic models, employing IHC, immunofluorescence, and hematoxylin and eosin staining for assessment. Results HRH1 expression in cancer cells was negatively correlated with HLA-ABC expression, CD8+ T cells, and cytotoxic CD8+ T cells. Our findings indicate that HRH1 blockade upregulates MHC-I expression in PCCs via cholesterol biosynthesis signaling. In the orthotopic model, the combined inhibition of HRH1 and αPD-1 blockade enhanced cytotoxic CD8+ T cell penetration and efficacy, overcoming resistance to ICB therapy. Conclusions HRH1 plays an immunosuppressive role in cancer cells. Consequently, HRH1 intervention may be a promising method to amplify the responsiveness of PDAC to immunotherapy.

Abstract Background Minimally invasive distal pancreatectomy (MIDP), including laparoscopic and robotic distal pancreatectomy, has gained widespread acceptance over the last decade owing to its favorable short-term outcomes. However, evidence regarding its oncologic safety is insufficient. In March 2023, a randomized phase III study was launched in Japan to confirm the non-inferiority of overall survival in patients with resectable pancreatic cancer undergoing MIDP compared with that of patients undergoing open distal pancreatectomy (ODP). Methods This is a multi-institutional, randomized, phase III study. A total of 370 patients will be enrolled from 40 institutions within 4 years. The primary endpoint of this study is overall survival, and the secondary endpoints include relapse-free survival, proportion of patients undergoing radical resection, proportion of patients undergoing complete laparoscopic surgery, incidence of adverse surgical events, and length of postoperative hospital stay. Only a credentialed surgeon is eligible to perform both ODP and MIDP. All ODP and MIDP procedures will undergo centralized review using intraoperative photographs. The non-inferiority of MIDP to ODP in terms of overall survival will be statistically analyzed. Only if non-inferiority is confirmed will the analysis assess the superiority of MIDP over ODP. Discussion If our study demonstrates the non-inferiority of MIDP in terms of overall survival, it would validate its short-term advantages and establish its long-term clinical efficacy. Trial registration This trial is registered with the Japan Registry of Clinical Trials as jRCT 1,031,220,705 [ https://jrct.niph.go.jp/en-latest-detail/jRCT1031220705 ].

Abstract Background Left-sided portal hypertension including gastric venous congestion may be caused by ligating the splenic vein during pancreaticoduodenectomy with portal vein resection or total pancreatectomy. The usefulness of reconstruction with the splenic vein has been reported in such cases. However, depending on the site of the tumor and other factors, it may be impossible to leave sufficient length of the splenic vein, making anastomosis difficult. We report two patterns of reconstruction with the right gastroepiploic vein during pancreaticoduodenectomy and total pancreatectomy to prevent left-sided portal hypertension. Case presentation The first patient was a 79-year-old man who underwent pancreaticoduodenectomy for pancreatic cancer. The root of the splenic vein was infiltrated by the tumor, and we resected this vein at the confluence of the portal vein. Closure of the portal vein was performed without reconstruction of the splenic vein. To prevent left-sided portal hypertension, we anastomosed the right gastroepiploic vein to the middle colic vein. Postoperatively, there was no suggestion of left-sided portal hypertension, such as splenomegaly, varices, and thrombocytosis. The second case was a 63-year-old woman who underwent total pancreatectomy for pancreatic cancer. The splenic vein–superior mesenteric vein confluence was infiltrated by the tumor, and we resected the portal vein, including the confluence. End-to-end anastomosis was performed without reconstruction of the splenic vein. We also divided the left gastric vein, left gastroepiploic vein, right gastroepiploic vein, and right gastric vein, which resulted in a lack of drainage veins from the stomach and severe gastric vein congestion. We anastomosed the right gastroepiploic vein to the left renal vein, which improved the gastric vein congestion. Postoperatively, imaging confirmed short-term patency of the anastomosis site. Although the patient died because of tumor progression 8 months after the surgery, no findings suggested left-sided portal hypertension, such as varices. Reconstruction with the right gastroepiploic vein during pancreaticoduodenectomy and total pancreatectomy is useful to prevent left-sided portal hypertension.

Abstract Background There are several options for the treatment of gastrointestinal stricture, including endoscopic stent placement and bypass surgery. However, a benign stricture is difficult to manage in a reconstructed gastric tube in the thoracic cavity owing to the technical difficulty of bypass surgery, and the possibility of stent migration. Case presentation A 78-year-old woman was admitted to our hospital for treatment for her inability to eat. She had undergone video-assisted subtotal esophagectomy with retromediastinal gastric tube reconstruction 7 years earlier. At the current admission, there was a severely dilated gastric tube in the thoracic cavity with a soft stricture immediately anterior to the spine. Conservative therapy was ineffective; therefore, endoscopic stenting was performed. However, the stent migrated to the upper side of the stricture because the stricture was mild, and the stent was not fixed in the gastric tube. Next, endoscopic stent placement followed by laparoscopic stent fixation was performed. The stent was patent and worked well, and the patient’s body weight increased. However, the stent collapsed 2 years later, with recurrence of symptoms. Stent-in-stent placement with an over-the-scope clip was performed, and the second stent was also patent and worked well. Conclusions Laparoscopic stent fixation with endoscopic stent placement could be an effective option for patients with a benign stricture in the reconstructed gastric tube.

Background: Malnutrition impacts the clinical course of Crohn's disease; however, there is little evidence of its influence on perioperative adverse events. We assessed whether nutritional indicators are associated with postoperative complications in surgical treatment of Crohn's disease. Methods: 137 patients with Crohn's disease who underwent surgical treatment between January 2011 and December 2020 were included. Skeletal muscle index was calculated by a single CT slice. We analyzed the risk factors for adverse events. Results: 37 % of patients had postoperative complications. Adverse events occurred more frequently in patients with high serum C-reactive protein, low serum albumin, prognostic nutritional index

Abstract Background Pancreatic ductal adenocarcinoma (PDAC) has a high mortality rate owing to its late diagnosis and aggression. In addition, there are relatively few minimally invasive screening methods for the early detection of PDAC, making the identification of biomarkers for this disease a critical priority. Recent studies have reported that microRNAs in extracellular vesicles (EV‐miRs) from bodily fluids can be useful for the diagnosis of PDACs. Given this, we designed this study to evaluate the utility of cancer EVs extracted from duodenal fluid (DF) and their resident EV‐miRs as potential biomarkers for the detection of PDAC. Methods EV‐miRs were evaluated and identified in the supernatants of various pancreatic cancer cell lines (Panc‐1, SUIT2, and MIAPaca2), human pancreatic duct epithelial cells, and the DF from patients with PDAC and healthy controls. EVs were extracted using ultracentrifugation and the relative expression of EV‐miR‐20a was quantified. Results We collected a total of 34 DF samples (27 PDAC patients and seven controls) for evaluation and our data suggest that the relative expression levels of EV‐miR‐20a were significantly higher in patients with PDAC than in controls (p = 0.0025). In addition, EV‐miR‐20a expression could discriminate PDAC from control patients regardless of the location of the tumor with an area under the curve values of 0.88 and 0.88, respectively. Conclusions We confirmed the presence of EVs in the DF and suggest that the expression of EV‐miR‐20a in these samples may act as a potential diagnostic biomarker for PDAC.

Abstract Background Palliative endoscopic stent placement may be considered in patients with malignant gastrointestinal obstruction. Stent migration is a potential complication, particularly for those placed at a surgical anastomosis or across a stricture caused by extra-alimentary tract factors. We report a patient with left renal pelvis cancer and gastrojejunostomy obstruction who underwent endoscopic stent placement and laparoscopic stent fixation. Case presentation A 60-year-old male with peritoneal dissemination of a left renal pelvis cancer was admitted for treatment of upper gastrointestinal obstruction. A laparoscopic gastrojejunostomy had been previously performed for cancer invasion of the duodenum. Imaging showed gastroduodenal dilation and impaired passage of contrast medium through the efferent loop of the gastrojejunostomy. Gastrojejunostomy anastomosis site obstruction due to dissemination of left renal pelvis cancer was diagnosed. Conservative treatment failed and endoscopic stent placement with laparoscopic stent fixation was performed. After surgery, the patient was able to tolerate oral intake and he was discharged without complications. The patient gained weight and was able to resume chemotherapy, indicating the procedure was effective. Conclusions Endoscopic stent placement with laparoscopic stent fixation for malignant upper gastrointestinal obstruction appears effective in patients with a high risk of stent migration.

Abstract Background There are few reports describing the unusual origin of the inferior mesenteric artery (IMA). We report a rare case of advanced sigmoid colon cancer with the IMA arising from the superior mesenteric artery. Case presentation A 59-year-old man with diarrhea and abdominal distention was diagnosed with advanced sigmoid colon cancer. Colonoscopy revealed a semi-circumferential cancer lesion in the sigmoid colon. Enhanced CT scan and CT angiography showed that the IMA directly originated from the superior mesenteric artery at the level of the second lumbar vertebra. PET-CT suggested metastases in the para-intestinal lymph nodes and the liver, but not in the central lymph nodes along the IMA. Preoperative diagnosis was sigmoid colon cancer cT4aN2aM1a cStage IVA(UICC, 8th edition). We performed laparoscopic complete resection as the radical treatment of the primary region prior to resection of the liver metastases. Intraoperative findings showed that the IMA was running parallel to the abdominal aorta; meanwhile, the colonic autonomic nerve was supplied from the lumbar splanchnic nerve at the caudal side of the duodenum. Central lymph nodes around the colonic autonomic nerve were dissected en bloc with the regional lymph nodes. Pathological radical resection including the regional lymph nodes metastasis was achieved. Two months later, complete resection of the liver metastasis was performed. After the adjuvant chemotherapy, no recurrence was observed 1.5 years after the liver resection was performed. Conclusions Preoperative confirmation of the anatomy helped us to safely complete radical surgery in a patient with unusual bifurcation of the IMA.

Abstract Aim The International Study Group for Pancreatic Surgery (ISGPS) developed a structured definition of postpancreatectomy acute pancreatitis (PPAP) in 2021. This study aimed to evaluate the clinical significance of PPAP as defined by the ISGPS criteria. Methods We evaluated the medical records and postoperative computed tomography (CT) findings of 247 patients who underwent pancreaticoduodenectomy. Postoperative hyperamylasemia (POH) was defined as an elevation in serum amylase levels over the upper baseline limit (≥133 U/L) on postoperative days 1 and 3. PPAP was defined as acute pancreatitis satisfying the following three requirements: POH, clinically relevant deterioration, and radiologic features consistent with acute pancreatitis. Results Postoperative hyperamylasemia and PPAP were prevalent in 9.7% (24/247) and 3.6% (9/247) of the patients, respectively. PPAP grade B occurred in eight patients, seven of whom experienced Clavien–Dindo grade IIIA complications, including postoperative pancreatic fistula (POPF) and extended periods of postoperative hospitalization. PPAP grade C occurred in one patient, who died from the exacerbation of underlying interstitial pneumonia following the POPF occurrence. Acute pancreatitis determined by CT was observed in 15.3% (38/247) of the patients who underwent pancreaticoduodenectomy and was strongly associated with severe morbidity (P

Abstract Purpose The distribution of tissue infiltrating lymphocytes has been shown to affect the prognosis of patients with pancreatic cancer in some previous studies. However, the role of peripheral lymphocytes in pancreatic cancer remains debated. The purpose of this study was to analyze the peripheral subtypes of T lymphocytes, and establish their association with the prognosis of patients with pancreatic cancer. Methods Blood and tissue samples were collected from patients with metastatic pancreatic cancer (n = 54), resectable pancreatic cancer (n = 12), and benign pancreatic cysts (n = 52) between April 2019 and January 2022 and analyzed. Results Patients with metastatic pancreatic cancer had a larger proportion of both tumor-suppressive and tumor-promoting cells than those with benign pancreatic cysts. In addition, the proportion of peripheral CD4+ T cells positively correlated with the survival of patients with metastatic pancreatic cancer, and the proportion of peripheral CD8+CD122+ T cells was associated with early mortality (

Purpose Preoperative sarcopenia worsens postoperative outcomes in various cancer types including colorectal cancer. However, we often experienced postoperative anastomotic leakage in muscular male patients such as Judo players, especially in rectal cancer surgery with lower anastomosis. It is controversial whether the whole skeletal muscle mass impacts the potential for anastomotic failure in male rectal cancer patients. Thus, the purpose of this study was to clarify whether skeletal muscle mass impacts anastomotic leakage in rectal cancer in men. Methods We reviewed the medical charts of male patients suffering from rectal cancer who underwent colo-procto anastomosis below the peritoneal reflection without a protective diverting stoma. We measured the psoas muscle area and calculated the psoas muscle index. Results One hundred ninety-seven male rectal cancer patients were enrolled in this study. The psoas muscle index was significantly higher in patients with anastomotic leakage (P

Objective: To determine the interobserver variability for complications of pancreatoduodenectomy as defined by the International Study Group for Pancreatic Surgery (ISGPS) and others. Background: Good interobserver variability for the definitions of surgical complications is of major importance in comparing surgical outcomes between and within centers. However, data on interobserver variability for pancreatoduodenectomy-specific complications are lacking. Methods: International cross-sectional multicenter study including 52 raters from 13 high-volume pancreatic centers in 8 countries on 3 continents. Per center, 4 experienced raters scored 30 randomly selected patients after pancreatoduodenectomy. In addition, all raters scored 6 standardized case vignettes. This variability and the "within centers" variability were calculated for 2-fold scoring (no complication/grade A vs grade B/C) and 3-fold scoring (no complication/ grade A vs grade B vs grade C) of postoperative pancreatic fistula, postpancreatoduodenectomy hemorrhage, chyle leak, bile leak, and delayed gastric emptying. Interobserver variability is presented with Gwet AC-1 measure for agreement. Results: Overall, 390 patients after pancreatoduodenectomy were included. The overall agreement rate for the standardized cases vignettes for 2-fold scoring was 68% (95% CI: 55%--81%, AC1 score: moderate agreement), and for 3-fold scoring 55% (49%--62%, AC1 score: fair agreement). The mean "within centers" agreement for 2-fold scoring was 84% (80%--87%, AC1 score; substantial agreement). Conclusions: The interobserver variability for the ISGPS-defined complications of pancreatoduodenectomy was too high even though the "within centers" agreement was acceptable. Since these findings will decrease the quality and validity of clinical studies, ISGPS has started efforts aimed at reducing the interobserver variability. [ABSTRACT FROM AUTHOR]

Abstract Background Pancreatic ductal adenocarcinoma (PDAC) is characterized by abundant stroma in which microenvironmental (niche) factors promote PDAC progression. In mouse models, reduction of the stroma increased the proportion of poorly differentiated PDAC with a worse prognosis. Here, we aimed to clarify the effects of stroma on PDAC that may define the PDAC phenotype and induce distinct therapeutic responses. Methods The molecular features of PDAC based on differentiation grade were clarified by genome and transcriptome analysis using PDAC organoids (PDOs). We identified the dependency on niche factors that might regulate the differentiation grade. A three-dimensional co-culture model with cancer-associated fibroblasts (CAFs) was generated to determine whether CAFs provide niche factors essential for differentiated PDAC. PDOs were subtyped based on niche factor dependency, and the therapeutic responses for each subtype were compared. Results The expression profiles of PDOs differed depending on the differentiation grade. Consistent with the distinct profiles, well differentiated types showed high niche dependency, while poorly differentiated types showed low niche dependency. The three-dimensional co-culture model revealed that well differentiated PDOs were strongly dependent on CAFs for growth, and moderately differentiated PDOs showed plasticity to change morphology depending on CAFs. Differentiated PDOs upregulated the expression of mevalonate pathway-related genes correlated with the niche dependency and were more sensitive to simvastatin than poorly differentiated PDOs. Conclusions Our findings suggest that CAFs maintain the differentiated PDAC phenotype through secreting niche factors and induce distinct drug responses. These results may lead to the development of novel subtype-based therapeutic strategies.

Summary: Although chemotherapy has been an essential treatment for cancer, the development of immune checkpoint blockade therapy was revolutionary, and a comprehensive understanding of the immunological tumor microenvironment (TME) has become crucial. Here, we investigated the impact of neoadjuvant chemotherapy (NAC) on immune cells in the TME of human esophageal squamous cell carcinoma using single cell RNA-sequencing. Analysis of 30 fresh samples revealed that CD8+/CD4+ T cells, dendritic cells (DCs), and macrophages in the TME of human esophageal squamous cell carcinoma showed higher levels of an anti-tumor immune response in the NAC(+) group than in the NAC(−) group. Furthermore, the immune cells of the NAC(+) group interacted with each other resulting in enhanced anti-tumor immune response via various cytokines, including IFNG in CD8+/CD4+ T cells, EBI3 in DCs, and NAMPT in macrophages. Our results suggest that NAC potentially enhances the anti-tumor immune response of immune cells in the TME.

Abstract Background/Aims Recently neoadjuvant chemotherapy (NAC) for pancreatic cancer has been shown to be superior to upfront surgery, but it remains a matter of debate for resectable cases. In clinical practice, some resectable cases may become unresectable after NAC. This study aimed to reveal the outcomes after NAC and to clarify the characteristics of unresected cases. Methods The medical records of 142 patients who underwent NAC between 2016 and 2020 were retrospectively reviewed. Patient characteristics, effectiveness of NAC, and outcomes were compared between the surgical group and non-surgical group (NSG). Furthermore, the risk of recurrence limited to in the patients who received NAC with gemcitabine plus nab-paclitaxel, which were mostly administered in this cohort, following R0/R1 resection was assessed. Results The overall and R0 resection rates after NAC were 89.1% and 79.7%, respectively. The neutrophil to lymphocyte ratio (NLR) > 2.78 (p = 0.0120) and anatomical borderline resectable pancreatic cancer (p = 0.0044) revealed a statistically significantly correlation with the NSG. On the other hand, NAC week IIA (P = 0.0003) were significantly associated with recurrence. The tumor response rate was approximately 26.1%, and three patients with ≥ 30% reduction of primary tumor lost excision opportunities because of metastasis, interstitial pneumonia, and vascular invasion. Conclusions This study shows incomplete tumor shrinkage benefits, but pre-NAC NLR is a predictive factor for predicting operability after NAC. The NLR can be easily calculated by normal blood test, and can be considered as a suitable marker of operability.

Abstract Background Tumour immune microenvironment is related with carcinogenesis and efficacy of immunotherapy. B cells play major roles in humoral immunity, but detailed functions of tumour‐infiltrating B lymphocytes (TIL‐Bs) are unknown. Therefore, our aim was to investigate the functional heterogeneity of TIL‐Bs in oesophageal squamous cell carcinoma (ESCC) and lymph nodes (LNs) during chemotherapy. Methods Single‐cell transcriptome analysis was performed on 23 specimens. We also performed immunohistochemical analysis of immunoglobulin κ C (IGKC), an antibody‐secreting cell (ASC) marker, in 166 ESCC samples and evaluated the implication of IGKC in 2‐year recurrence free survival (RFS) and 3‐year overall survival (OS). Results A total of 81,246 cells were grouped into 24 clusters. We extracted B cell clusters based on canonical markers and identified 12 TIL‐B subtypes in ESCC. We found that several functions, such as co‐stimulation and CD40 signalling, were enhanced in TIL‐Bs after chemotherapy. The proportion of naive B cells (NBCs) decreased and B cell activation genes were up‐regulated in NBCs after chemotherapy. The proportion of ASCs in tumours increased with the loss of migratory abilities and antibody production in ASCs was promoted after chemotherapy. Differentially expressed genes up‐regulated with chemotherapy in ASCs correlated with prolonged survival with oesophageal cancer (p = .028). In a metastatic LN, the ASC proportion increased and B cell differentiation was enhanced. In immunohistochemical analysis, RFS and OS of high IGKC expression cases were significantly better than those of low IGKC expression cases (RFS: p

Abstract Robotic surgery has emerged as an alternative to laparoscopic surgery and it has also been applied to pancreatectomy. With the increase in the number of robotic pancreatectomies, several studies comparing robotic pancreatectomy and conventional open or laparoscopic pancreatectomy have been published. However, the use of robotic pancreatectomy remains controversial. In this review, we aimed to provide a comprehensive overview of the current status of robotic pancreatectomy. Various aspects of robotic pancreatectomy and conventional open or laparoscopic pancreatectomy are compared, including the benefits, limitations, oncological efficacy, learning curves, and costs. Both robotic pancreatoduodenectomy and distal pancreatectomy have favorable or comparable outcomes to conventional procedures, and robotic pancreatectomy has the potential to be an alternative to open or laparoscopic procedures. However, there are still several disadvantages to robotic platforms, such as prolonged operative duration and the high cost of the procedure. These disadvantages will be improved by developing instruments, overcoming the learning curve, and increasing the number of robotic pancreatectomies. In addition, robotic pancreatectomy is still in the introductory period in most centers and should only be used in accordance with strict indications.

Abstract Background Pancreatic stellate cells (PSCs) occupy the majority of the pancreatic cancer microenvironment, contributing to aggressive behavior of pancreatic cancer cells (PCCs). Recently, anti-fibrotic agents have proven to be an effective strategy against cancer, but clinical trials have shown little efficacy, and the driving mechanism remains unknown. N-acetyl-cysteine (NAC) is often used for pulmonary cystic fibrosis. Pioglitazone, an agonist of peroxisome proliferator-activated receptor gamma, was habitually used for type II diabetes, but recently reported to inhibit metastasis of PCCs. However, few studies have focused on the effects of these two agents on cancer-stromal interactions. Method We evaluated the expression of α-smooth muscle actin (α-SMA) and the number of lipid droplets in PSCs cultured with or without NAC. We also evaluated changes in invasiveness, viability, and oxidative level in PSCs and PCCs after NAC treatment. Using an indirect co-culture system, we investigated changes in viability, invasiveness, and migration of PSCs and PCCs. Combined treatment effects of NAC and Pioglitazone were evaluated in PSCs and PCCs. In vivo, we co-transplanted KPC-derived organoids and PSCs to evaluate the effects of NAC and Pioglitazone’s combination therapy on subcutaneous tumor formation and splenic xenografted mouse models. Results In vitro, NAC inhibited the viability, invasiveness, and migration of PSCs at a low concentration, but not those of PCCs. NAC treatment significantly reduced oxidative stress level and expression of α-SMA, collagen type I in PSCs, which apparently present a quiescent-like state with a high number of lipid droplets. Co-cultured PSCs and PCCs mutually promoted the viability, invasiveness, and migration of each other. However, these promotion effects were attenuated by NAC treatment. Pioglitazone maintained the NAC-induced quiescent-like state of PSCs, which were reactivated by PCC-supernatant, and enhanced chemosensitivity of PCCs. In vivo, NAC and Pioglitazone’s combination suppressed tumor growth and liver metastasis with fewer stromal components and oxidative stress level. Conclusion NAC suppressed activated PSCs and attenuated cancer-stromal interactions. NAC induces quiescent-like PSCs that were maintained in this state by pioglitazone treatment.

Abstract Aim As the prognosis of patients who undergo resection for pancreatic cancer has improved, reports of remnant pancreatic cancer after pancreatic cancer resection have been increasing. Previous studies regarding early‐stage pancreatic cancer showed a high incidence of remnant pancreatic cancer in these patients. The aim of this study was to investigate the incidence of remnant pancreatic cancer according to the degree of progression of the initial pancreatic cancer. Methods Patients who underwent partial pancreatic resection for primary pancreatic cancer were retrospectively reviewed and divided into an early‐stage group and an advanced‐stage group according to the stage of the initial cancer. Patient characteristics and long‐term outcomes, including development of remnant pancreatic cancer, were compared between the two groups. Results This study included 321 patients who underwent partial pancreatectomy for pancreatic cancer; 32 patients in the early‐stage group and 289 patients in the advanced‐stage group. Remnant pancreatic cancer developed in 19 patients (5.9%); seven patients (21.9%) in the early‐stage group and 12 patients (4.5%) in the advanced‐stage group. The cumulative incidence of remnant pancreatic cancer according to the Kaplan–Meier method was comparable between the two groups (5‐year cumulative incidence: 20.6% vs 9.9%, early‐stage group vs advanced‐stage group; P = .1827). Conclusion Our results suggested that the potential for developing remnant pancreatic cancer was comparable between the early‐stage and the advanced‐stage groups. Therefore, the incidence of remnant pancreatic cancer may increase along with improved pancreatic cancer treatment.

A 2-year-old Maltese was presented with wobbly gait of the pelvic limbs. Based on imaging examinations, a diagnosis of congenital malformation at T5–T8 and severe kyphosis causing spinal cord compression at T6–T7 was made. Dorsal laminectomy and stabilization of T6 and T7 vertebrae were performed. As the size of the vertebrae was small and they were severely deformed, novel custom-made titanium implants were used for spinal stabilization. Clinical signs were resolved 2 weeks after surgery. Although radiographic examination 373 days after surgery showed slight loosening of implants, post-operative course remained uneventful. This report describes the use of novel custom-made titanium implants for spinal fixation surgery in a dog.

Case summary A 2-year-old neutered female Scottish Fold cat was presented with an 8-week history of progressive back pain, paraparesis and decrease of postural reactions in both pelvic limbs. MRI showed spinal cord compression from both ventral sides, which originated from the T4 vertebral body and pedicle. The lesion compressing the spinal cord had a bone-like density on CT, and endoscopic surgery was performed to excise it. Histopathological examination of the resected tissue showed no evidence of malignancy and the lesion was diagnosed as vertebral hypertrophy. After surgery, the neurological status of the cat gradually improved. The cat was ambulant at the follow-up evaluation 2 weeks after surgery. Six months later, hindlimb paresis had improved considerably, and no recurrence was observed on CT. Relevance and novel information This is the first description of thoracic vertebral canal stenosis due to hypertrophy of a single vertebra in a young cat. Excision of the hypertrophic vertebra by endoscopic surgery is less invasive than open surgery and may give a good prognosis.

Abstract Background Degenerative myelopathy (DM) is a progressive neurodegenerative disease frequently found in Pembroke Welsh Corgis (PWCs). Most DM-affected PWCs are homozygous for the mutant superoxide dismutase 1 (SOD1) allele; however, the genetic examination for the SOD1 mutation does not exclusively detect symptomatic dogs. In order to identify novel biomarkers, the plasma microRNA (miRNA) profiles of PWCs with DM were investigated. Results Quantification of the plasma levels of 277 miRNAs by an RT-qPCR array identified 11 up-regulated miRNAs and 7 down-regulated miRNAs in DM-affected PWCs from those in wild-type SOD1 PWCs. A pathway analysis identified 3 miRNAs: miR-26b, miR-181a, and miR-196a, which potentially regulate several genes associated with SOD1. In order to validate the diagnostic accuracy of the candidate miRNAs in the aged PWC population, candidate miRNAs in plasma were measured by RT-qPCR and a receiver operating characteristic (ROC) curve analysis was performed. miR-26b had the largest area under the ROC curve for distinguishing DM PWCs from healthy PWCs (sensitivity, 66.7%; specificity, 87.0%). The plasma level of miR-26b was significantly higher in the DM group than in the healthy control group. A positive correlation was observed between increases in the plasma level of miR-26b and disease progression. Conclusions These results suggest that plasma miR-26b is a potential novel diagnostic biomarker of DM.

Abstract Background Extracellular signal-regulated kinases (ERKs) have been related to multiple cancers, including breast cancer, hepatocellular cancer, lung cancer and colorectal cancer. ERK1/2 inhibitor can suppress growth of KRAS-mutant pancreatic tumors by targeting cancer cell. However, no studies have shown the expression of ERK1/2 on pancreatic stromal and its effect on pancreatic cancer–stromal interaction. Methods Immunohistochemistry and western blotting were performed to detect the expression of p-ERK1/2 in pancreatic tissues and cells. Cell viability assay was used to study IC50 of ERK inhibitor on pancreatic cancer cells (PCCs) and primary cancer-associated pancreatic stellate cells (PSCs). Transwell migration, invasion, cell viability assay, senescence β-galactosidase staining were performed to determine the effect of ERK inhibitor on PCCs and PSCs in vitro and in vivo. The expression of key factors involved in autophagy and epithelial-to-mesenchymal transition (EMT) process were evaluated by western blotting. The expression of key factors related to cell invasiveness and malignancy were confirmed by qRT-PCR. Co-transplantation of PCC Organoid and PSC using a splenic xenograft mouse model was used to evaluated combined treatment of ERK inhibitor and autophagy inhibitor. Results Immunohistochemical staining in pancreatic tumor samples and transgenetic mice detected p-ERK1/2 expression in both cancer cells and stromal cells. In pancreatic tissues, p-ERK1/2 was strongly expressed in cancer-associated PSCs compared with cancer cells and normal PSCs. PSCs were also significantly more sensitive to ERK1/2 inhibitor treatment. Inhibition of ERK1/2 suppressed EMT transition in HMPCCs, upregulated cellular senescence markers, activated autophagy in cancer-associated PSCs; and suppressed cancer–stromal interaction, which enhanced invasiveness and viability of cancer cells. We also found that chloroquine, an autophagy inhibitor, suppressed ERK inhibition-induced autophagy and promoted PSC cellular senescence, leading to significantly decreased cell proliferation. The combination of an ERK inhibitor and autophagy inhibitor suppressed liver metastasis in a splenic pancreatic cancer organoid xenograft mouse model. Conclusions These data indicate that inhibition of ERK1/2 in cancer-associated pancreatic stellate cells suppresses cancer–stromal interaction and metastasis.

This case series describes transoral penetrating or contusive medullocervical injury by a wooden chopstick in three young cats presenting with acute tetraparesis. CT revealed that remnant fragments of a wooden chopstick penetrated the atlantooccipital space in cases 1 and 2. The remnant fragments were visualized clearly on CT under the bone window setting. MRI revealed a hyper-intense lesion in the spinal cord parenchyma at the level of C1 on T2-weighted images in case 3. Tetraparesis improved after surgical removal of the remnant fragment in case 2 and with supportive care in case 3.

A 4-month-old cat with epileptic seizures and nasal discharge was presented, and diagnosed with intranasal meningoencephalocele based on the clinical symptoms and findings of CT and MRI. As liquorrhea was suspected, the meningoencephalocele was surgically excised and the postoperative course was favorable. For cribriform plate reconstruction, the autologous tunica vaginalis was used. Rhinorrhea of the cerebrospinal fluid and seizures disappeared after surgery. On CT and MRI at 7 months after surgery, septum formation between the cranial and nasal cavities was confirmed. Currently, no seizures have occurred even though no oral antiepileptic agent was administered. There are few reports of surgical treatment for meningoencephalitis, and there are no reports of reconstruction of the cribriform plate using tunica vaginalis, so we reported the details.

Abstract Background Intraductal tubulopapillary neoplasm (ITPN) is a rare pancreatic intraductal neoplasm. It is characterized by a tubulopapillary growth pattern, entirely high-grade atypical cells, minimal cytoplasmic mucin, and no obvious luminal mucin secretion. Most of its biological nature remains unclear. Case presentation We herein report a case of intrapancreatic recurrence of ITPN in the remnant pancreas of a patient who underwent pancreatoduodenectomy 16 years previously for a noninvasive intraductal pancreatic head tumor. We reexamined the primary tumor and compared it with the most recently resected specimen. Histologically, the primary tumor showed a tubulopapillary growth of high-grade atypical cells with scanty cytoplasmic mucin, which was similar to the recently resected specimen except for the invasive area. Immunohistochemically, the neoplastic cells in both specimens showed focal staining of MUC1 and positivity for MUC6 but negativity for MUC2, MUC5AC, CDX2, and trypsin. Molecular analysis revealed no KRAS/GNAS/BRAF/PIK3CA mutations in either of the specimens. Conclusions These findings of the original tumor and recently resected tumor were compatible with the features of ITPN. Thus, recurrence is possible even for a primary noninvasive ITPN, and long-term surveillance is recommended.

Endoscopic management is presently the recommended first-line of treatment for biliary strictures. However, surgery still has an important role especially for biliary obstruction (BO) with duodenal obstruction. Even though endoscopic treatment for concurrent BO and gastric-outlet obstruction has been proposed, it is still not widespread. Duodenal obstruction is often associated with malignant BO which makes endoscopic treatment more challenging. Biliary and gastrointestinal double bypass with Roux-en-Y hepaticojejunostomy and gastrojejunostomy is the most common surgical intervention for malignant biliary and gastric-outlet obstruction. A variety of procedures of biliary bypass and gastrointestinal bypass have been reported. According to several studies, mortality rates range from 0% to 7%, while morbidity rates range from 3% to 50%. Higher morbidity was observed in symptomatic patients caused by the disease. Most common morbidity after double bypass was delayed gastric emptying. Recurrence of BO and gastric-outlet obstruction was less frequently seen after surgical bypass compared to after endoscopic treatment. Minimally invasive approach has been applied to double bypass. Studies showed that laparoscopic double bypass has a shorter hospital stay and reduced postoperative pain; however, due to its technical demand, it is still presently an uncommon procedure. Robotic bypass surgery may resolve this issue in the future. Further analyses of outcomes of both surgical and endoscopic treatments are necessary to establish better and suitable palliation options for concurrent biliary and duodenal obstruction caused by unresectable malignant tumors.

The objective of this study was to evaluate the feasibility and clinical outcomes of microendoscopic dorsal laminectomy for multi-level cervical intervertebral disc protrusions in dogs. Eight client-owned dogs diagnosed with multi-level cervical intervertebral disc protrusions using computed tomography (CT) and magnetic resonance imaging (MRI) were included in this retrospective case series. Microendoscopic dorsal laminectomies (MEL) were performed with an integrated endoscopic system to the cranial and caudal vertebrae of the affected intervertebral joints. Pre- and post-operative neurological status, operation time, intra-operative complications, and postoperative complications were reviewed. Post-operative CT images were obtained to measure the dimensions of laminectomy and compared to those of planned laminectomy. Full endoscopic procedures were feasible in 7 dogs (87.5%) and the laminectomy dimensions were in agreement with pre-operative planning. In all dogs, major intra- and postoperative complications did not occur. Conversion to open surgery was required in one case. Short-term postoperative clinical deterioration was found in two dogs. Long-term clinical outcomes were good and comparable to those reported in previous studies of open dorsal laminectomies. MEL is a promising minimally invasive approach to multi-level cervical dorsal laminectomy for intervertebral disc protrusions. This technique may improve postoperative discomfort compared to the open approach. Further studies are needed to directly compare outcomes between these two approaches.

The objective of this study was to evaluate the clinical outcomes and complications of a microendoscopic laminectomy and discectomy (MED) for acute thoracolumbar intervertebral disc extrusions in dogs. Eleven client-owned dogs with acute thoracolumbar intervertebral disc extrusions were included in this retrospective case-series. Dogs were diagnosed with acute thoracolumbar intervertebral disc extrusions using computed tomography (CT) and magnetic resonance imaging (MRI). MED was performed with an integrated endoscopic system to the affected intervertebral disc. Surgery time, intra-operative complications, causes of conversion to microscopic surgery if necessary, post-operative complications, and neurological status on presentation at discharge, as well as any further evaluations in hospital, and long-term concerns via owner contact, were recorded. Post-operative CT images were obtained to compare the extent of laminectomy performed to the planned region of laminectomy. The fully endoscopic procedure was completed in eight dogs without major complications. Three cases were converted to an open surgery due to difficulty removing extruded disc material and controlling hemorrhage. The clinical outcome was good in all cases and equivalent to previously reported prognoses after open surgery. MED is an effective and safe alternative to conventional open procedures in dogs with acute thoracolumbar intervertebral disc extrusion.

Canine degenerative myelopathy (DM), recognized as a spontaneous model of amyotrophic lateral sclerosis, is known as a late-onset progressive degenerative disease of the spinal cord. Because of the progressive nature of DM, many dogs are elected to be euthanized, resulting in limited information on the end-stage clinical presentation. We investigated the long-term clinical course from diagnosis to natural death to further deepen our understanding of the entire clinical picture of this disease. Because curcumin was administered in some cases, the therapeutic effect of curcumin on DM was also examined. Forty dogs included in this study were client-owned Pembroke Welsh Corgis with a definitive diagnosis of DM by necropsy and histopathology. Dogs were excluded from this study if they died from another disease or were elected to be euthanized. Information on the long-term clinical symptoms of DM was investigated based on a questionnaire, which was collected from the dog owners. Urinary incontinence and respiratory disorder were observed in most dogs, as was respiratory impairment-correlated death. In contrast, signs consistent with brainstem dysfunction were noticed at the terminal stage in a small portion of dogs. Although further studies with more cases are needed, the results of this study suggest that administration of curcumin is effective in slowing the progression of DM.

BACKGROUND:Necroptosis is a form of programmed cell death that is accompanied by release of intracellular contents, and reportedly contributes to various diseases. Here, we investigate the significance of necroptosis in pancreatic cancer. METHODS:We used immunohistochemistry and western blot analysis to evaluate expression of the key mediators of necroptosis-receptor-interacting serine/threonine protein kinase 3 (RIP3) and mixed lineage kinase domain-like (MLKL)-in human pancreatic cancer. We also tested the effects of conditioned media (CM) from necroptotic cells on pancreatic cancer cells in Transwell migration and Matrigel invasion assays. Protein array analysis was used to investigate possible mediators derived from necroptotic cells. RESULTS:RIP3 and MLKL are highly expressed in human pancreatic cancer tissues compared with normal pancreas. MLKL expression was particularly intense at the tumor invasion front. CM derived from necroptotic cells promoted cancer cell migration and invasion, but not CM derived from apoptotic cells. C-X-C motif chemokine 5 (CXCL5) was upregulated in CM derived from necroptotic cells compared with CM derived from control or apoptotic cells. Moreover, expression of the receptor for CXCL5, C-X-C-motif chemokine receptor-2 (CXCR2), was upregulated in pancreatic cancer cells. Inhibition of CXCR2 suppressed cancer cell migratory and invasive behavior enhanced by necroptosis. CONCLUSION:These findings indicate that necroptosis at the pancreatic cancer invasion front can promote cancer cell migration and invasion via the CXCL5-CXCR2 axis.

Objectives: To develop drill guide templates as an intraoperative guide, and to evaluate the accuracy and safety of screw placement in the lumbosacral junction.Samples: Canine cadaveric specimens of the lumbosacral junction (n = 6), and clinical cases of lumbosacral instability (n = 3).Procedures: Computed tomography data of the lumbosacral region of cadaveric specimens and clinical cases were obtained. The optimum screw trajectories were determined and drill guide templates were fabricated using a three-dimensional printing system. Drill holes were made using the templates in cadaveric specimens and clinical cases, and lumbosacral fixation was performed in clinical cases. Computed tomography images were obtained to compare the planned and postoperative drill hole trajectories, and the accuracy and safety of drilling and screw placement in the lumbosacral junction were evaluated.Results: Thirty-six drill holes were made in cadaveric specimens. The overall mean drill hole deviation was 2.05 ± 1.32 mm. A total of 12 screws were placed in the lumbosacral junctions of three clinical cases. The overall mean drill hole deviation was 2.43 ± 1.09 mm. Clinical signs improved within 2 weeks in the clinical cases. All drill holes were completely located within the bone in cadaveric specimens and clinical cases.Conclusion and Clinical Relevance: The surgical procedures using the drill guide templates were performed safely with good clinical outcomes. The drill guide template system provided useful surgical guidance to safely and precisely perform screw placement for lumbosacral fixation surgery in small dogs.

Canine degenerative myelopathy (DM) is a progressive and fatal neurodegenerative disease. However, a definitive diagnosis of DM can only be achieved by postmortem histopathological examination of the spinal cord. The purpose of this study was to investigate whether the volumetry of DRG using the ability of water-excitation magnetic resonance imaging (MRI) to visualize the DRG in dogs has premortem diagnostic value for DM. Eight dogs with DM, twenty-four dogs with intervertebral disc herniation (IVDH), and eight control dogs were scanned using a 3.0-tesla MRI system, and water-excitation images were obtained to visualize and measure the volume of DRG, normalized by body surface area. The normalized mean DRG volume between each spinal cord segment and mean volume of all DRG between T8 and L2 in the DM group was significantly lower than that in the control and the IVDH groups (P = 0.011, P = 0.002, respectively). There were no correlations within the normalized mean DRG volume between DM stage 1 and stage 4 (rs = 0.312, P = 0.128, respectively). In conclusion, DRG volumetry by the water-excitation MRI provides a non-invasive and quantitative assessment of neurodegeneration in DRG and may have diagnostic potential for DM.