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Central pancreatectomy(CP) is more complex surgery and higher complication rate than distal pancreatectomy(DP). However, with the development of minimally invasive surgery, CP has become a safer surgery technique. In this study, we compare minimally invasive CP(MI-CP) and Minimally invasive spleen-preserving subtotal DP(MI-SpSTDP) to figure out the short-term and long-term outcomes of MI-CP.From March 2007 to June 2020, 36 cases of MI-SpSTDP and 23 cases of MI-CP were performed for benign and borderline malignant pancreatic tumors in Severance hospital. The occurrence of postoperative pancreatic fistula(POPF) and Clavian-Dindo classification grade 3 or more in the two group was investigated, and the Controlling nutritional status scores(CONUT score) before and 1-year after surgery were compared to determine the long-term outcomes of exocrine function.There was no difference in postoperative complications including POPF between the two groups(17.4% vs 5.1%, p = 0.294). And there were no statistical differences in either the MI-CP group (0.74 ± 0.75 vs. 0.78 ± 0.99, p = 0.803) or the MI-SpSTDP group (0.86 ± 0.83 to 0.61 ± 0.59, p = 0.071).MI-CP had longer operation time and hospital stay and is safe and effective in preserving endocrine and exocrine functions in treatment of benign or borderline tumors located at the neck or proximal body of the pancreas.

/Purpose: Owing to the characteristics of IPMNs, which have variable skipped lesions along the main pancreatic duct (MPD), determining the surgical margins is very difficult. This study aimed to investigate the efficacy and potential oncologic impact of intraoperative pancreatoscopy (IOP) compared to frozen section biopsy (FSB) in pancreaticoduodenectomy (PD) for pancreatic head IPMNs.Data of patients who underwent PD for IPMNs of the pancreas between October 2007 and May 2020 were retrospectively reviewed. IOP was performed in selected patients with IPMNs with inconclusive MPD involvement based on preoperative evaluations. Patients were divided into two groups, IOP group, FSB group. Clinicopathologic features and oncologic outcomes were compared between two groups.60 patients underwent PD (laparoscopic or robotic, 42; open, 18) for pancreatic head IPMNs. IOP was safely performed in 28 patients, including minimally invasive approach used in 21 patients (35%). IOP group had a significantly larger MPD size (9.15 ± 4.79 mm vs 6.43 ± 4.11 mm, p = 0.021). Based on IOP, the initial surgical plan could be changed in 5 patients (17.8%) for complete resection. Recurrence occurred in 2 patients in FSB group and 3 patients in IOP group during the follow-up period (33.2 months, [range, 3.5-131.4 months]). Overall disease-free survival rate did not significantly differ between two groups (p = 0.529).IOP can be safely performed in patients with pancreatic head IPMNs with MPD dilatation, even in the laparoscopic approach. Further studies evaluating the long-term oncologic effect of IOP for the management of IPMNs are required.

During pancreaticoduodenectomy after transhiatal esophagectomy, the preservation of the blood supply to the gastric conduit is technically difficult due to adhesion. Here, we present a case of successful pancreaticoduodenectomy after neoadjuvant chemotherapy in a patient with pancreatic head cancer who previously underwent subtotal esophagectomy with gastric reconstruction for esophageal cancer. A 69-year-old man who had undergone cholecystectomy 20 years prior and transhiatal esophagectomy 6 years prior for esophageal cancer presented to our hospital for indigestion. Computed tomography and magnetic resonance imaging revealed a 2.8-cm pancreatic head cancer, with focal abutment with the gastroduodenal artery, right gastroepiploic artery, and right colic vein. After discussion with the multidisciplinary team, the patient underwent neoadjuvant chemotherapy with six cycles of FOFIRINOX. The patient successfully underwent pancreatectomy, which preserved the pylorus. We preserved the gap between the gastric tube and the left lateral segment of the liver to avoid injuring the right gastric artery and vein. The tumor was found to be invading the gastroduodenal artery; thus, we performed R0 resection of the gastroduodenal artery and an end-to-end anastomosis between the gastroduodenal artery and the right gastroepiploic artery. After completing the surgical procedure, we added Braun anastomosis to reduce the incidence of delayed gastric emptying. Pancreaticoduodenectomy after transhiatal esophagectomy can be performed with preservation of the blood supply to the neogastric tube by reconstructing the major vessels, even in cases in which the tumor is invading or abutting the major vessels.

Minimally invasive pancreaticoduodenectomy (MIPD) is a challenging procedure. Laparoscopic pancreaticoduodenectomy (LPD) is feasible and safe. Since the development of robotic platforms, the number of reports on robot-assisted pancreatic surgery has increased. We compared the technical feasibility and safety between LPD and robot-assisted LPD (RALPD).From September 2012 to August 2020, 257 patients who underwent MIPD for periampullary tumors were enrolled. Of these, 207 underwent LPD and 50 underwent RALPD. We performed a 1:1 propensity score-matched (PSM) analysis and retrospectively analyzed the demographics and surgical outcomes.After PSM analysis, no difference was noted in demographics. Operation times and estimated blood loss were similar, as was the incidence of complications (p 0.05). In subgroup analysis in patients with soft pancreas with pancreatic duct ≤ 2 mm, no significant between-group difference was noted regarding short-term surgical outcomes, including clinically relevant POPF (CR-POPF) (p 0.05). In multivariable analysis, the only soft pancreatic texture was a predictive factor (HR 3.887, 95% confidence interval 1.121-13.480, p = 0.032).RALPD and LPD are safe and effective for MIPD and can compensate each other to achieve the goal of minimally invasive surgery.

Neighborhood disadvantage is a developmental context that may contribute to Asian American adolescent internalizing problems, yet there is a dearth of longitudinal studies as well as examination of cultural protective factors. Co-ethnic density, or the proportion of individuals of the same racial/ethnic background in the neighborhood that is often cited as a protective factor for racial/ethnic minority groups, has not been adequately examined in Asian American youth. This study examined the longitudinal association between cumulative neighborhood risk and internalizing behavior, and the moderating role of sex and co-ethnic density using an Asian American subsample (N = 177; 45.2% female; ages 10-12, 14-15; Cambodian, Chinese, Filipino, Hmong, Japanese, Korean, Laotian, Samoan, Vietnamese, and other ethnic backgrounds) of a longitudinal panel study over a span of 6 years. Cumulative neighborhood risk during early adolescence (ages 10-14) was significantly associated with internalizing behavior at mid-adolescence (age 15) controlling for prior levels of internalizing behavior. There was no evidence of moderation by co-ethnic density or sex, indicating that reducing neighborhood disadvantage may be a promising preventive measure to address mental health problems for both sexes of Asian American adolescents.

Childhood adversities have a well-established dose–response relationship with later mental health. However, less attention has been given to intergenerational influences. Further, it is unknown how intergenerational influences intersect with children’s developmental stages and gender. The current study examined whether a developmental inflection point exists when the intergenerational influences of childhood adversities gain salience and explored differences by children’s gender. Data were from the Young Women and Child Development Study (n = 361). Time-varying effect models (TVEMs) and moderation TVEMs by child’s gender were evaluated. Our findings reveal that ages 5–8, the period of transition into primary schools, may represent a developmental inflection point when the intergenerational influences of maternal childhood adversity start emerging substantially. The results from gender interaction TVEMs reveal that maternal childhood adversity was a statistically significant predictor of internalizing problems until age 11, regardless of child’s gender, and remained statistically significant for girls’ internalizing problems until age 16.7. For externalizing problems, maternal childhood adversity was a statistically significant predictor until age 13, regardless of gender.

Background/aims : Controversy regarding the effectiveness of neoadjuvant therapy for resectable pancreatic ductal adenocarcinoma (PDAC) still exists. Here, we aimed to identify the potential benefits of neoadjuvant therapy followed by surgery for resectable PDAC. Methods We reviewed radiologically resectable PDAC patients who received resection with curative intent at a tertiary hospital in South Korea between January 2012 and August 2019. A total of 202 patients underwent curative resection for resectable PDAC: 167 underwent surgical resection first during this period, and 35 received neoadjuvant chemotherapy/chemoradiation therapy followed by surgery. Resectable PDAC patients were subdivided, and 1:3 propensity score matching (PSM) was performed to reduce selection bias. Results Compared with the group that received surgery first, the group that received neoadjuvant treatment followed by surgery had significantly smaller tumors (22.0 mm vs 27.0 mm, p=0.004), a smaller proportion of patients with postoperative pathologic T stage (p=0.026), a smaller proportion of patients with lymphovascular invasion (20.0% vs 40.7%, p=0.022), and a larger proportion of patients with negative resection margins (74.3% vs 51.5%, p=0.049). After PSM, the group that received neoadjuvant therapy had a significantly longer progression-free survival than those in the group that underwent surgery first (29.6 months vs 15.1 months, p=0.002). Overall survival was not significantly different between the two groups after PSM analysis. Conclusions We observed significantly better surgical outcomes and progression-free survival with the addition of neoadjuvant therapy to the management of resectable PDAC. However, despite PSM, there was still selection bias due to the use of different regimens between the groups receiving surgery first and neoadjuvant therapy. Large homogeneous samples are needed in the future prospective studies.

Introduction Pancreatic cancer is a devastating disease with a high relapse rate, even in resectable pancreatic cancer. This study aimed to identify the prognostic significance and therapeutic chance of the metabolic subtypes for resectable pancreatic cancer. Methods We obtained transcriptomic data from the TCGA-PAAD cohort via the The Cancer Genome Atlas (TCGA) data portal (n = 182). After integrative analysis of transcriptomic data in the discovery cohort, immunohistochemical (IHC) staining was performed in the independent cohort to validate the molecule of interest. Experimental testing for the molecule of interest was performed using pancreatic cancer cell lines, including AsPC1, BxPC3, MIA PaCa-2, and PANC-1 in vitro. Results Two subtypes showing distinct gene expression patterns in the TCGA-PAAD dataset were identified. The active glucose metabolism subtype showed significantly lower survival regarding cancer relapse after surgical resection. The genes SLC2A1 (GLUT1) and SLC16A3 (MCT4) were highly enriched in the active metabolism subtype. The validation cohort showed high IHC staining intensity for MCT4 and a significantly high relapse rate (p = 0.01). Several molecular pathways associated with aggressive tumor biology regarding cell cycle, Myc, and mTOR downstream signaling were highly enriched in the high glucose uptake subtype as well as distinct response for immunotherapy. MCT4 inhibition suppressed pancreatic cancer cell lines in vitro and showed a synergetic effect with gemcitabine treatment. Conclusions MCT4 was identified from integrative analysis as a potential therapeutic target in resectable pancreatic cancer. The precision strategy for resectable pancreatic cancer should be validated in a clinical setting with a prospective study design.

Background/aims Several prediction models for evaluating the prognosis of nonmetastatic resected pancreatic ductal adenocarcinoma (PDAC) have been developed, and their performances were reported to be superior to that of the 8th edition of the American Joint Committee on Cancer (AJCC) staging system. We developed a prediction model to evaluate the prognosis of resected PDAC and externally validated it with data from a nationwide Korean database. Methods Data from the Surveillance, Epidemiology and End Results (SEER) database were utilized for model development, and data from the Korea Tumor Registry System-Biliary Pancreas (KOTUS-BP) database were used for external validation. Potential candidate variables for model development were age, sex, histologic differentiation, tumor location, adjuvant chemotherapy, and the AJCC 8th staging system T and N stages. For external validation, the concordance index (C-index) and time-dependent area under the receiver operating characteristic curve (AUC) were evaluated. Results Between 2004 and 2016, data from 9,624 patients were utilized for model development, and data from 3,282 patients were used for external validation. In the multivariate Cox proportional hazard model, age, sex, tumor location, T and N stages, histologic differentiation, and adjuvant chemotherapy were independent prognostic factors for resected PDAC. After an exhaustive search and 10-fold cross validation, the best model was finally developed, which included all prognostic variables. The C-index, 1-year, 2-year, 3-year, and 5-year time-dependent AUCs were 0.628, 0.650, 0.665, 0.675, and 0.686, respectively. Conclusions The survival prediction model for resected PDAC could provide quantitative survival probabilities with reliable performance. External validation studies with other nationwide databases are needed to evaluate the performance of this model.

We carried out KF postdeposition treatment (PDT) on a Cu(In,Ga)Se2 (CIGS) layer with a process time varying from 50 to 200 s. The highest CIGS solar-cell efficiency was achieved at a KF PDT process time of 50 s; in this condition, we observed the highest level of K element at the near-surface of the CIGS layer and the perfectly passivated pinholes on the CIGS surface. At process times above 150 s, the oversupplied KF agglomerated into large islands and was subsequently eliminated during the deposition of the chemical bath deposition (CBD)-Zn(O,S) buffer layer owing to the islands' water-soluble characteristics. As a result, the growth mechanism of the CBD-Zn(O,S) layer varied as a function of KF PDT process time. X-ray photoemission spectroscopy (XPS) measurements were used to examine the dependency of the chemical state on the KF PDT process time, and from the results, we formulated a chemical reaction model based on the shift in the elemental binding energy following deposition of the CBD-Zn(O,S) buffer layer. The chemical states of the K-In-Se phase, which have a beneficial effect on the solar-cell performance owing to the formation of durable and improved p-n junctions, are formed only at a KF PDT process time of 50 s. We derived band alignments from the XPS depth profiles by extracting the conduction- and valence-band offsets, and we used optical-pump-THz-probe spectroscopy to measure the ultrafast photocarrier lifetimes related to the defect states following KF PDT. Our key findings can be summarized as follows: (i) photocarrier transport is beneficial at a low barrier height, and (ii) the photocarrier lifetime increases when the K-In-Se phases are formed on the CIGS surface, which allows K+ ions to be effectively substituted into Cu vacancies.

Laparoscopic pancreatoduodenectomy (LPD) in pancreatic cancer is primarily criticized for its technical and oncological safety. Although solid evidence has not yet been established, many institutions are performing LPD for pancreatic cancer patients, with continuous efforts to ensure oncologic safety. In this video, we demonstrated a case of standard LPD combined with vascular resection in pancreatic cancer.

The aim of this study was to examine how perceived racial discrimination is associated with mental distress among diverse Asian Americans and to explore the potential moderators in the relationship. Based on the 2015 Asian American Quality of Life (AAQoL) survey (n = 2609), direct influences were tested of the contextual (demographic, health-related, and immigration-related) variables and perceived racial discrimination on mental distress, as well as their interactions. About 30% of the sample reported perceived racial discrimination, and 44% fell into the category of having mental distress. Perceived racial discrimination was associated with 1.90 times higher odds of mental distress and had significant interactions with age, education, and ethnicity. The association of mental distress with perceived racial discrimination was higher among those who were 60 or older, less educated, and Vietnamese than among their respective counterparts. Findings can guide strategic and targeted interventions for high-risk groups.

The hypothalamic kisspeptin/KISS1 receptor system is essential for puberty onset and reproductive development. Although serum kisspeptin might be associated with puberty, its levels, according to developmental stage, and its origin still remain unclear. This study evaluated the changes in serum kisspeptin levels during puberty and the corresponding Kiss1 mRNA and protein expression in various organs of female rats to identify the source of serum kisspeptin. Tissues from several organs, including the ovaries and anteroventral periventricular nucleus (AVPV) and arcuate nucleus (ARC) in the hypothalamus, were obtained for assessing Kiss1 mRNA and protein expressions. Serum kisspeptin levels progressively increased with developmental stages until the peripubertal stage. The ovaries showed the highest Kiss1 expression among the organs examined. Next, we explored the changes in serum kisspeptin levels and hypothalamic Kiss1 expression in ovariectomized and estradiol-treated ovariectomized rats. Serum kisspeptin levels decreased regardless of estradiol treatment; Kiss1 expression was enhanced by ovariectomy and estradiol treatment in the ARC, while it was decreased by ovariectomy and enhanced by estradiol in the AVPV, suggesting that serum kisspeptin may be associated with pubertal development and mainly depended on ovarian Kiss1 expression. Thus, serum kisspeptin levels are associated with puberty and may serve as a downstream marker of ovarian reproductive function.

Insulin-like growth factor binding protein-3 (IGFBP-3) has been known to inhibit the proliferation of various cell types in an insulin-like growth factor (IGF)-independent manner. In this study, we aimed to show that IGFBP-3 induces cellular senescence via suppression of telomerase activity, thereby inhibiting cancer cell proliferation. We found that the induction of IGFBP-3 in MCF-7 cells inhibited cell proliferation. Flow cytometry revealed that the percentage of non-cycling cells was higher in IGFBP-3-expressing cells than in controls. Induction of IGFBP-3 also resulted in morphological changes, such as a flattened cytoplasm and increased granularity, suggesting that IGFBP-3 induces senescence-like phenotype. The percentage of cells containing senescence-associated β-galactosidase activity was 3.3 times higher in IGFBP-3 expressing cells compared to control cells. Telomeric repeat amplification and real-time PCR showed that IGFBP-3 decreased telomerase activity by decreasing the expression of the RNA component (hTR) and catalytic protein component with reverse transcriptase activity (hTERT) of telomerase. These results suggest that IGFBP-3 functions as a negative regulator of breast cancer cell growth by inducing a senescence through the inhibition of telomerase activity.

BACKGROUND AND AIMS Biliary tract cancer (BTC) exhibits diverse molecular characteristics. However, reliable biomarkers that predict therapeutic responses are yet to be discovered. We aimed to identify the molecular features of treatment responses to chemotherapy and immunotherapy in BTCs. APPROACH AND RESULTS We enrolled 121 advanced BTC patients (68 cholangiocarcinomas [33 intrahepatic, 35 extrahepatic], 41 gallbladder cancers, and 12 Ampulla of Vater cancers) whose specimens were analyzed by clinical sequencing platforms. All patients received first-line palliative chemotherapy; 48 patients underwent programmed death 1 (PD-1)/programmed death-ligand 1 (PD-L1) blockade therapy after failed chemotherapy. Molecular and histopathological characterization was performed using targeted sequencing and immunohistochemical staining to investigate treatment response-associated biomarkers. Genomic analysis revealed a broad spectrum of mutational profiles according to anatomical location. Favorable responses to chemotherapy were observed in the small-duct type compared with the large-duct type intrahepatic cholangiocarcinoma, with frequent mutations in BRCA1-associated protein-1/isocitrate dehydrogenase 1/2 and KRAS proto-oncogene, GTPase/SMAD family member 4 genes, respectively. The molecular features were further analyzed in BTCs, and transforming growth factor beta and DNA damage response pathway-altered tumors exhibited poor and favorable chemotherapy responses, respectively. In PD-1/PD-L1 blockade-treated patients, KRAS alteration and chromosomal instability tumors were associated with resistance to immunotherapy. The majority of patients (95.0%) with these resistance factors show no clinical benefit to PD-1/PD-L1 blockade and low tumor mutational burdens. Low tumor-infiltrating lymphocyte (TIL) density in tumors with these resistance factors indicated immune-suppressive tumor microenvironments, whereas high intratumoral TIL density was associated with a favorable immunotherapy response. CONCLUSIONS This study proposes predictive molecular features of chemotherapy and immunotherapy responses in advanced BTCs using clinical sequencing platforms. Our result provides an intuitive framework to guide the treatment of advanced BTCs benefiting from therapeutic agents based on the tumors' molecular features.

Background: This study aims to evaluate sinistral portal hypertension (SPH) development and its clinical impact on the long-term outcomes of patients with pancreatic cancer who underwent surgical resection with splenic vein (SV) ligation. Methods: Data from 94 consecutive patients who underwent pancreatoduodenectomy (PD) with vascular resection for pancreatic cancer from 2008 to 2019 were retrospectively collected. The patients were divided into two groups according to whether the SV was preserved or ligated during the surgery. Their computed tomography images were serially reviewed (preoperative, 6-, 12-, and 24-months postoperative) with clinical parameters. The degree of variceal formation (variceal score) and splenomegaly were assessed, and the oncologic outcomes were compared between the two groups. Variceal score in the SV ligation group was significantly higher than that in the SV saving group at the same postoperative periods (SV saving vs. ligation: 12 months, 0.9 ± 1.3 vs. 3.5 ± 2.2, p < 0.001; 24 months, 1.4 ± 1.8 vs. 4.0 ± 3.4, p = 0.009). Clinically relevant variceal bleeding was noted in one patient from the SV ligation group (SV saving vs. ligation: 0.0% vs. 3.1%, p = 0.953). In survival analysis, there was no significant difference between the two groups (DFS; SV saving vs. ligation: 13.0 (11.1–14.9) months vs. 13.0 (10.4–15.6) months, p = 0.969, OS; SV saving vs. ligation: 35.0 (19.9–50.1) months vs. 27.0 (11.6–42.4) months, p = 0.417). Although SV ligation induced SPH during PD for pancreatic cancer, it did not lead to clinically significant long-term complications. In addition, it did not impact the long-term survival of patients with resected pancreatic head cancer.

Pancreatic cancer is one of the dismal malignant disease in gastrointestinal tract. However, since the recent literature reporting median survival of FOLFIRINOX (leucovorin clcium, fluorouracil, irinotecan hydrochloride, oxaliplatin) chemotherapy was more than 12 months in metastatic pancreatic cancer was published, the positive attitude toward the treatment of the advanced pancreatic cancer is gradually expanded among the medical and surgical oncologists. Due to multiple combination of potent chemotherapeutic agents, potential adverse side effects should be concerned when considering FOLFIRINOX. Herein, we report a 55-year old male patient with locally advanced pancreatic cancer who successfully underwent curative resection following by laparoscopic division of pancreaticosplenic ligament due to long-term preoperative use of FOLFIRINOX related hepatic toxicity associated with secondary hypersplenism. The present case suggests the extended radical PD with combined major vascular resection following laparoscopic division of pancreaticosplenic ligament containing splenic artery and vein can improve the safety of curative resection and may expand the potential indication of pancreatic cancer in well-selected long-term use of preoperative FOLFIRINOX induced hepatic toxicity associated with secondary hypersplenism.

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.

Background Since margin-negative resection is essential for the cure of pancreatic cancer (PC), early detection of PC is important. Although PC is the third most common cancer associated with BRCA1/2 mutations, clinical research regarding BRCA mutations in resected PC are rare. In this study, we investigated the oncologic characteristics of resected PC with BRCA mutation to suggest management strategies. Methods We retrospectively reviewed data from 493 patients who were confirmed to be pathogenic BRCA1/2 mutation carriers between January 2007 and December 2019. We investigated the oncologic characteristics of PC patients by comparing them with resected sporadic PC and other BRCA-related cancer groups (breast cancer, ovarian cancer, and others). Results Ten BRCA mutation carriers (2.0%) experienced PC, and PC onset was significantly later than that of BRCA-related breast cancer (age: breast vs. pancreas, 45.0 vs. 53.5 years, p = 0.050). Six patients underwent pancreatectomy and their long-term survival outcomes did not differ from those of sporadic PC patients (disease free survival: BRCA1/2 vs. sporadic, 10.0 months vs. 9.0 months, p = 0.504; overall survival: BRCA1/2 vs. sporadic, 29.0 months vs. 35.0 months, p = 0.520). Conclusion BRCA-mutated PC occurs later than BRCA-mutated breast cancer. Active genetic testing to identify BRCA1/2 mutation carriers at the onset of breast cancer and continuous long-term surveillance of these patients can provide opportunities to detect BRCA-mutated PC at a resectable stage.

We investigated the effects of H+ ion irradiation on a chalcogenide Cu(In,Ga)Se2 (CIGS) thin film as a function of the dose concentration (1014 ∼ 1016/cm2) at 200 keV by using time-resolved THz spectroscopy. The optical conductivity of these films was derived from THz time-domain spectroscopy (THz-TDS) in the THz region. THz emission spectroscopy revealed the emission of a strong-intensity THz pulse from the H+ ion-irradiated CIGS thin film. This is explained by considering the ultrafast behavior of photocarriers, resulting in strong surface band bending induced by the built-in potential with a conversion of the CIGS thin film from p - to n -type. Finally, we used optical pump THz probe spectroscopy to examine the ultrafast photocarrier dynamics determined by the time of capture at the increased number of surface and bulk defect states. This clearly showed that irradiation with H+ ions could generate a number of defect states while simultaneously pacifying the Cu vacancy defects.

Backgrounds/aims Minimally invasive surgery is a widely accepted approach in hepatobiliary surgery and choledochal cyst excision has also been performed by minimally invasive methods, including laparoscopic and robotic approaches. However, only a few studies have compared laparoscopic and robotic surgery. Therefore, we performed a comparative study between two groups, including cost aspects. Methods We retrospectively analyzed minimally invasive choledochal cyst excision at Severance Hospital in Seoul, South Korea from January 2005 to December 2018. A total of 39 patients that underwent minimally invasive choledochal cyst excision were identified. The 23 patients (58.9%) and 16 patients (41.1%) were enrolled in laparoscopic and robotic approach, respectively. We compared the patient's characteristics, and perioperative outcomes between laparoscopic and robotic surgery groups. Results A comparative analysis between the two groups showed no differences in preoperative clinical characteristics. There were no significant differences in operative time, estimated blood loss, and postoperative complications, including biliary complication. The preoperative ASA score (p=0.021) and hospital stays (p=0.011) were the only clinical variables that differed between the two groups. All of the variables included in the cost analysis showed statistically significant differences (total hospital charge: p=0.035, patient's bill: p≤0.001, operation: p=0.002, anesthesia: p=0.001, postoperative management: p=0.001). Conclusions The overall clinical outcomes between the laparoscopic and robotic approach to choledochal cyst were comparable. The surgical approach should be balanced based on the surgeons' skill, patients' general condition, disease extent, and economic status.

Background Postoperative pancreatic fistula (POPF) and postoperative fluid collection (POFC) are common complications after distal pancreatectomy (DP). The previous method of reducing the risk of POPF was the application of a polyglycolic acid (PGA) sheet to the pancreatic stump after cutting the pancreas with a stapler (After-stapling); the new method involves wrapping the pancreatic resection line with a PGA sheet before stapling (Before-stapling). The study aimed to compare the incidence of POPF and POFC between two methods. Methods Data of patients who underwent open or laparoscopic DPs by a single surgeon from October 2010 to February 2020 in a tertiary referral hospital were retrospectively analyzed. POPF was defined according to the updated International Study Group of Pancreatic Fistula criteria. POFC was measured by postoperative computed tomography (CT). Results Altogether, 182 patients were enrolled (After-stapling group, n = 138; Before-stapling group, n = 44). Clinicopathologic and intraoperative findings between the two groups were similar. Clinically relevant POPF rates were similar between both groups (4.3% vs. 4.5%, p = 0.989). POFC was significantly lesser in the Before-stapling group on postoperative day 7 (p Conclusions Wrapping the pancreas with PGA sheet before stapling was a simple and effective way to reduce POFC.

This study aimed to validate and compare the performance of the original fistula risk scores (o-FRS), alternative (a-FRS), and updated alternative FRS (ua-FRS) after open pancreatoduodenectomy (OPD) and laparoscopic pancreatoduodenectomy (LPD) in an Asian patient cohort.Data of 597 consecutive patients who underwent PD (305 OPD, 274 LPD) were collected from two tertiary centers. Model performance was assessed using the area under the receiver operating curve (AUC).The overall AUC values of o-FRS, a-FRS, and ua-FRS were 0.67, 0.69, and 0.68, respectively, which were lower than those of the Western validation. Three FRS systems had similar AUC values in the overall and OPD groups, whereas ua-FRS had a higher AUC than o-FRS in the LPD group. The accuracy of ua-FRS (47.2%) was higher than that of o-FRS (39.0%) and a-FRS (19.5%) overall, but low specificity and low positive predictive value were observed regardless of the operative type across the three FRS systems. In the multivariate analysis, pathology, estimated blood loss, and body mass index were not independent risk factors for CR-POPF in the OPD and LPD groups.Current FRS systems have some limitations, including a relatively lower performance in an Asian cohort, low positive predictive values, and inclusion of insignificant risk factors.

Pancreatic cancer is one of the most lethal malignant diseases in gastrointestinal system that only about 15-20% of the patients are potential candidates for resection at diagnostic stage. However, with the advent of neoadjuvant chemotherapy and advancement of surgical skills, patients with locally advanced pancreatic cancer (LAPC), which were deemed initially unresectable, have undergone margin negative radical resection. Here, we present a case of a patient with LAPC who was previously treated with neoadjuvant FOLFIRINOX and underwent pancreaticoduodenectomy combined with vascular resection after preoperative percutaneous transhepatic portal vein stent placement to relieve of portal vein obliteration. The patient recovered without any complication and was discharged on day 8 postoperatively.