Three Molecular Developmental Pathways of Remnant Pancreatic Cancer after Resection: A Nationwide Project Study of Japan Pancreas Society.

OBJECTIVE: This study aimed to clarify the molecular mechanism of remnant pancreatic cancer (PC) development after primary PC resection. SUMMARY BACKGROUND DATA: Molecular mechanisms of the development of remnant PCs following primary PC resection are largely unknown. METHODS: Forty-three patients undergoing remnant PC resection after primary PC resection between 2001 and 2017 at 26 institutes were retrospectively analyzed. Clinicopathological features and molecular alterations detected by targeted amplicon sequencing of 36 PC-associated genes were evaluated. RESULTS: These patients showed significantly lower body mass indices and higher hemoglobin A1c values at remnant PC resection than at primary PC resection. A comparison of the molecular features between primary and remnant PCs indicated that remnant PCs were likely to develop via three different molecular pathways: successional, showing identical and accumulated alterations (n=14); phylogenic, showing identical and distinct alterations (n=26); and distinct, showing independent distinctive alterations (n=3). The similarity of gene alterations was associated with time to the remnant PC development (r=－0.384, P=0.0173). Phylogenic pathways were significantly associated with the intraductal spread of carcinoma (P=0.007). Patient survival did not differ significantly depending on these molecular pathways. CONCLUSION: Molecular profiling uncovered three pathways for the development of remnant PCs, namely, successional, phylogenic, and distinct pathways. The vast majority of remnant PCs are likely to be molecularly associated with primary PCs either in the successional or phylogenic way. This information could impact the design of a strategy for monitoring and treating remnant PCs.

Conversion surgery for initially unresectable locally advanced biliary tract cancer: A multicenter collaborative study conducted in Japan and Korea.

BACKGROUND: Although surgical resection is the only curative treatment for biliary tract cancer, in some cases, the disease is diagnosed as unresectable at initial presentation. There are few reports of conversion surgery after the initial treatment for unresectable locally advanced biliary tract cancer. This study aimed to evaluate the efficacy and safety of conversion surgery in patients with initially unresectable locally advanced biliary tract cancer. METHODS: We retrospectively collected clinical data from groups of patients in multiple centers belonging to the Japanese Society of Hepato-Biliary-Pancreatic Surgery and Korean Association of Hepato-Biliary-Pancreatic Surgery. We analyzed two groups of prognostic factors (pretreatment and surgical factors) and their relation to the treatment outcomes. RESULTS: A total of 56 patients with initially unresectable locally advanced biliary tract cancer were enrolled in this study of which 55 (98.2%) patients received chemotherapy, and 16 (28.6%) patients received additional radiation therapy. The median time from the start of the initial treatment to resection was 6.4 months. Severe postoperative complications of Clavien-Dindo grade III or higher occurred in 34 patients (60.7%), and postoperative mortality occurred in five patients (8.9%). Postoperative histological results revealed CR in eight patients (14.3%). The median survival time from the start of the initial treatment in all 56 patients who underwent conversion surgery was 37.7 months, the 3-year survival rate was 53.9%, and the 5-year survival rate was 39.1%. CONCLUSIONS: Conversion surgery for initially unresectable locally advanced biliary tract cancer may lead to longer survival in selected patients. However, more precise preoperative safety evaluation and careful postoperative management are required.

Factors Affecting Nonfunctioning Small Pancreatic Neuroendocrine Neoplasms and Proposed New Treatment Strategies.

BACKGROUND & AIMS: Despite previously reported treatment strategies for nonfunctioning small (≤20 mm) pancreatic neuroendocrine neoplasms (pNENs), uncertainties persist. We aimed to evaluate the surgically resected cases of nonfunctioning small pNENs (NF-spNENs) in a large Japanese cohort to elucidate an optimal treatment strategy for NF-spNENs. METHODS: In this Japanese multicenter study, data were retrospectively collected from patients who underwent pancreatectomy between January 1996 and December 2019, were pathologically diagnosed with pNEN, and were treated according to the World Health Organization 2019 classification. Overall, 1490 patients met the eligibility criteria, and 1014 were included in the analysis cohort. RESULTS: In the analysis cohort, 606 patients (59.8%) had NF-spNENs, with 82% classified as grade 1 (NET-G1) and 18% as grade 2 (NET-G2) or higher. The incidence of lymph node metastasis (N1) by grade was significantly higher in NET-G2 (G1: 3.1% vs G2: 15.0%). Independent factors contributing to N1 were NET-G2 or higher and tumor diameter ≥15 mm. The predictive ability of tumor size for N1 was high. Independent factors contributing to recurrence included multiple lesions, NET-G2 or higher, tumor diameter ≥15 mm, and N1. However, the independent factor contributing to survival was tumor grade (NET-G2 or higher). The appropriate timing for surgical resection of NET-G1 and NET-G2 or higher was when tumors were >20 and >10 mm, respectively. For neoplasms with unknown preoperative grades, tumor size >15 mm was considered appropriate. CONCLUSIONS: NF-spNENs are heterogeneous with varying levels of malignancy. Therefore, treatment strategies based on tumor size alone can be unreliable; personalized treatment strategies that consider tumor grading are preferable.

Short-term serial circulating tumor DNA assessment predicts therapeutic efficacy for patients with advanced pancreatic cancer.

PURPOSE: We investigated the potential clinical utility of short-term serial KRAS-mutated circulating cell-free tumor DNA (ctDNA) assessment for predicting therapeutic response in patients undergoing first-line chemotherapy for advanced pancreatic cancer. METHODS: We collected 144 blood samples from 18 patients with locally advanced or metastatic cancer that were undergoing initial first-line chemotherapy of gemcitabine plus nab-paclitaxel (GEM plus nab-PTX). Analysis of KRAS-mutated ctDNA was quantified by digital droplet polymerase chain reaction (ddPCR) as mutant allele frequency (MAF). This study investigated pretreatment KRAS-mutated ctDNA status and ctDNA kinetics every few days (days 1, 3, 5 and 7) after initiation of chemotherapy and their potential as predictive indicators. RESULTS: Of the 18 enrolled patients, an increase in KRAS-mutated ctDNA MAF values from day 0-7 after initiation of chemotherapy was significantly associated with disease progression (P < 0.001). Meanwhile, positive pretreatment ctDNA status (MAF ≥ 0.02%) (P = 0.585) and carbohydrate antigen 19-9 (CA19-9) values above the median (P = 0.266) were not associated with disease progression. In univariate analysis, this short-term increase in ctDNA MAF values (day 0-7) was found to be associated with significantly shorter progression free survival (PFS) (hazard ration [HR], 24.234; range, (2.761-212.686); P = 0.0002). CONCLUSION: This short-term ctDNA kinetics assessment may provide predictive information to reflect real-time therapeutic response and lead to effective refinement of regimen in patients with advanced pancreatic cancer undergoing systemic chemotherapy.

Days of the week and 90-day mortality after esophagectomy: analysis of 33,980 patients from the National Clinical Database.

PURPOSE: The effect of the days of the week on the short-term outcomes after elective surgeries has been suggested; however, such data on esophagectomies remain limited. This study aimed to investigate the association between the day of the week and mortality rates after elective esophagectomy using a large-scale clinical database in Japan. METHODS: The data of elective esophagectomies, registered in the National Clinical Database in Japan, for esophageal cancer treatment between 2012 and 2017 were analyzed. We hypothesized that the later days of the week could have higher odds ratios of death after elective esophagectomy. With 22 relevant clinical variables and days of surgery, 90-day mortality was evaluated using hierarchical logistic regression modeling. RESULTS: Ninety-day mortality rates among 33,980 patients undergoing elective esophagectomy were 1.8% (range, 1.5-2.1%). Surgeries were largely concentrated on earlier days of the week, whereas esophagectomies performed on Fridays accounted for only 11.1% of all cases. Before risk adjustment, lower odds ratios of 90-day mortality were found on Tuesday and a tendency towards lower odds ratios on Thursday. In the hierarchical logistic regression model, 21 independent factors of 90-day mortality were identified. However, the adjusted odds ratios of 90-day mortality for Tuesday, Wednesday, Thursday, and Friday were 0.87, 1.09, 0.85, and 0.88, respectively, revealing no significant difference. CONCLUSION: The results imply that the variation in 90-day mortality rates after esophagectomy on different days of the week may be attributed to differing preoperative risk factors of the patient group rather than the disparity in medical care provided.

Neoadjuvant Triplet Chemotherapy with Docetaxel, Cisplatin plus 5-Fluorouracil versus Docetaxel, Cisplatin plus S-1 for Advanced Esophageal Squamous cell Carcinoma: Propensity Score Matched Analysis.

INTRODUCTION: This study examines whether neoadjuvant docetaxel, cisplatin plus S-1 (DCS) therapy is superior to docetaxel, cisplatin plus 5-fluorouracil (DCF) therapy for resectable advanced esophageal squamous cell carcinoma (ESCC). METHODS: Patients diagnosed with resectable advanced ESCC at our hospital between January 2010 and December 2019 underwent either neoadjuvant DCF therapy or DCS therapy, followed by radical esophagectomy. Prior to August 2014, we usually used neoadjuvant DCF therapy; we then completely transitioned to using neoadjuvant DCS therapy. RESULTS: A total of 144 patients received one of these triplet regimens as neoadjuvant chemotherapy: DCF therapy to 67 patients and DCS therapy to 77 patients. After propensity score matching, 55 patients in each group were selected as matched cohorts. There was no significant difference between the groups in complete response (DCF = 7.3%, DCS = 9.1%) or in partial response (DCF = 45.4%, DCS = 52.7%). The pathological response rate was 23.8% for grade 2 and 18.2% for grade 3 in the DCF group, compared with 30.9% and 14.5% in the DCS group. Independent predictive factors for recurrence-free survival were poor clinical response and pathological response ≤1b. Independent prognostic factors for overall survival were poor clinical response, anastomotic leakage, and pathological response ≤1b. Duration of hospital stays in the DCS group was significantly shorter than those of the DCF group (6.0 vs. 15.0 days, p < 0.001). Expenses of drug and hospitalization for the neoadjuvant chemotherapy in the DCS group were also significantly lower than those of the DCF group (265.7 vs. 550.3 USD, p < 0.001). CONCLUSIONS: Neoadjuvant DCS therapy for resectable advanced ESCC did not result in significantly higher clinical and pathological response than neoadjuvant DCF therapy. However, neoadjuvant DCS therapy for resectable ESCC required comparatively shorter hospital stays and incurred lower costs, making it an attractive therapeutic option.

Histone methyltransferase SUV420H1/KMT5B contributes to poor prognosis in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) has a high rate of recurrence and poor prognosis, even after curative surgery. Multikinase inhibitors have been applied for HCC patients, but their effect has been restricted. This study aims to clarify the clinical impact of SUV420H1/KMT5B, one of the methyltransferases for histone H4 at lysine 20, and elucidate the novel mechanisms of HCC progression. We retrospectively investigated SUV420H1 expression using HCC clinical tissue samples employing immunohistochemical analysis (n = 350). We then performed loss-of-function analysis of SUV420H1 with cell cycle analysis, migration assay, invasion assay and RNA sequence for Gene Ontology (GO) pathway analysis in vitro, and animal experiments with xenograft mice in vivo. The SUV420H1-high-score group (n = 154) had significantly poorer prognosis for both 5-year overall and 2-year/5-year disease-free survival than the SUV420H1-low-score group (n = 196) (p < 0.001 and p < 0.05, respectively). The SUV420H1-high-score group had pathologically larger tumor size, more tumors, poorer differentiation, and more positive vascular invasion than the SUV420H1-low-score group. Multivariate analysis demonstrated that SUV420H1 high score was the poorest independent factor for overall survival. SUV420H1 knockdown could suppress cell cycle from G1 to S phase and cell invasion. GO pathway analysis showed that SUV420H1 contributed to cell proliferation, cell invasion, and/or metastasis. Overexpression of SUV420H1 clinically contributed to poor prognosis in HCC, and the inhibition of SUV420H1 could repress tumor progression and invasion both in vitro and in vivo; thus, further analyses of SUV420H1 are necessary for the discovery of future molecularly targeted drugs.

Efficacy and safety of neoadjuvant nab-paclitaxel plus gemcitabine therapy in patients with borderline resectable pancreatic cancer: A multicenter single-arm phase II study (NAC-GA trial).

Background: Nab-paclitaxel plus gemcitabine is a standard treatment for metastatic/locally advanced pancreatic cancer. The effectiveness of neoadjuvant therapy with nab-paclitaxel plus gemcitabine (GnP-NAT) in patients with borderline resectable pancreatic cancer (BRPC) remains unclear. Patients and Methods: This single-arm phase II trial included 61 patients with BRPC that were treated with two cycles of GnP-NAT, (nab-paclitaxel 125 mg/m2 and gemcitabine 1000 mg/m2), on days 1, 8, and 15 over a 4-week period, which comprised one cycle. The primary endpoint was overall survival time. In the absence of disease progression, patients underwent planned pancreatectomy. Results: Median overall survival, the primary endpoint, was 25.2 months, and the median recurrence-free survival was 12.3 months. The overall rate of grade 3/4 events was 73.8%. One patient, who had a history of radiation therapy for past esophageal cancer, died from exacerbation via pneumonia. The overall resection rate was 73.8% (n = 45), and the R0 resection rate was 63.9% (n = 39). Overall, postoperative complications were found in 19 patients (42%) with 24 events, and nine patients (20%) with nine events ≥ grade IIIa, based on Dindo's classification. Conclusions: This protocol treatment is thought to be a feasible, safe, and promising treatment regimen, but we caution against its use in patients with a history of interstitial lung disease and/or prior pulmonary irradiation. The survival data from this study suggest the need for further investigations of GnP-NAT efficacy in patients with BRPC, as well as prospective evaluation of adverse events. Clinical Trial Registration: UMIN Clinical Trials Registry, UMIN000024154 and ClinicalTrials.gov, NCT02926183.

Central pancreatectomy might be an acceptable surgical procedure for clinical T1 pancreatic body ductal adenocarcinoma: A multicenter retrospective analysis.

BACKGROUND: Central pancreatectomy (CP) is accepted as a function-preserving procedure for benign tumors. However, the indication of CP for pancreatic cancers is limited. This multicenter study aimed to clarify the indications of CP for clinical T1 pancreatic body cancer. METHODS: This multicenter study analyzed patients who underwent CP or distal pancreatectomy (DP) for clinical T1 pancreatic body cancer between 2013 and 2020 at three high-volume centers. RESULTS: A total of 50 patients were enrolled: nine patients, who underwent CP, were classified into the CP group, while 38 patients, who underwent DP, served as controls. Three patients converted CP to DP during operation were excluded. Five patients in the CP group and 15 patients in the control group underwent preoperative treatment. The 5-year survival rate was 100% in the CP group, and 42% (p = .040) in the control group. Recurrence was found in three patients in the CP group. Importantly, insulin was not required after surgery in patients in the CP group. CONCLUSION: The clinical outcomes of CP were comparable to or even better than that of conventional pancreatectomy. Our collaborative study suggests that CP may be an acceptable therapeutic option for selected patients with clinical T1 pancreatic body cancer.

Impact of antithrombotic therapy on postpancreatectomy hemorrhage in 7116 patients: A project study by the Japanese Society of Hepato-Biliary-Pancreatic Surgery.

BACKGROUND: We previously reported an association between antithrombotic therapy and an increased risk of postpancreatectomy hemorrhage (PPH). To validate our findings, we conducted a large-scale multicenter retrospective study from 63 high-volume centers in Japan. METHODS: Between 2015 and 2018, 7116 patients who underwent pancreatectomy were enrolled. The antithrombotic group consisted of 920 patients (12.9%) who received preoperative antithrombotic agents including aspirin, clopidogrel, ticlopidine, prasugrel, warfarin, and direct oral anticoagulants. RESULTS: PPH occurred in 235 (3.3%) of the patients. The incidence of PPH and mortality were significantly higher in the antithrombotic group than in the control group (5.7 vs. 3.0% and 2.2 vs. 0.9%, respectively; both p < .001). In multivariate analysis, a history of antithrombotic use was an independent risk factor for grade C PPH (p = .036). In the antithrombotic group, PPH tended to be delayed in the patients with restarting antithrombotic therapy. Notably, the occurrence of delayed PPH after restarting antithrombotic therapy was observed only when antithrombotic therapy was restarted within 10 days after pancreatectomy. CONCLUSIONS: This multicenter study demonstrated that a history of antithrombotic use was a significant risk factor for PPH and mortality. In particular, the resumption of antithrombotic therapy in the early postoperative period should be done with caution.

Virtual Reality Images of the Home Are Useful for Patients With Hospital-Based Palliative Care: Prospective Observational Study With Analysis by Text Mining.

Background: Malignancy patients who need long-term hospitalization can feel loneliness affecting their quality of life. The global COVID-19 pandemic has caused visiting restrictions that could mean patients who might be missing out on family support and palliative care, therefore, need to adapt and change. We used virtual reality (VR) technology with the aim of reducing feelings of loneliness among these patients. Objectives: In a small cohort setting, we aimed to clarify the usefulness of VR viewing for this purpose by text mining interviews with the patients in palliative care after their VR experience, and to clarify the feasibility of this program. Design and Setting/Subjects: Four consecutive Japanese patients in the palliative care unit viewed personalized familiar persons or places through VR goggles, while communicating by telephone. After the VR experience, text mining of the patients' interviews was used to extract the words for the frequency count and co-occurrence analysis. Results: Four clusters were extracted: "relief from the pain of hospitalization by feeling safe and secure with family members nearby," "using VR to regain daily life," "immersive feeling of being in the same space as family," and "loneliness due to the realistic feeling of separation from the family through VR experience." There were no cases of VR sickness. Conclusion: Our results attained by text mining suggest the promising potential of VR imaging of familiar surroundings for patients in palliative care.

Randomized controlled trial comparing cosmetic results of midline incision versus off-midline incision for specimen extraction in laparoscopic colectomy.

PURPOSE: A notable advantage of laparoscopic colorectal surgery is that only a small incision at the extraction site is necessary, which is considered to be cosmetically beneficial. Meanwhile, the optimal extraction site for the resected specimen in laparoscopic colectomy is controversial in terms of cosmetic benefit. This randomized controlled trial compares midline and off-midline extraction sites in laparoscopic colectomy in patients with colon cancer, with consideration of cosmetic benefits as the primary endpoint. METHODS: Included were patients that underwent elective laparoscopic colectomy at WMUH between October 2014 and February 2017. Patients were randomly assigned to either midline incision group or off-midline incision group. Prospectively collected data included cosmetic results (patients and observer assessment scale) and complications including incidence of incisional hernia, SSI, and pain. This trial was registered with UMIN Clinical Trials (UMIN000028943). RESULTS: Finally, 98 patients with colorectal cancer were analyzed. No significant differences were found between the two groups in patient and observer assessment scales of cosmetic results (midline 8 ± 1.1 vs off-midline 11 ± 5.9 p = 0.16, midline 13.5 ± 6.6 vs off-midline 15 ± 11 p = 0.58, respectively) or in postoperative pain. However, incisional hernia occurred in four cases in the midline group (8%), which was significantly higher than that in the off-midline group (no cases, 0%). CONCLUSION: There was no significant difference in terms of cosmetic benefit, the primary endpoint, between the two groups. In this study, only the extraction site location was compared; future studies will examine differences depending on the incisional direction, including the incidence of incisional hernia.

Laparoscopic reconstruction in McKeown esophagectomy is a risk factor for postoperative diaphragmatic hernia.

Diaphragmatic hernia is a very rare but high-risk complication after esophagectomy. Although there are many studies on the Ivor Lewis esophagectomy procedure for diaphragmatic hernia, there are fewer studies on the McKeown procedure. The present study aimed to estimate the incidence of diaphragmatic hernia after esophagectomy, describing its presentation and management with the McKeown procedure. We retrospectively evaluated the 622 patients who underwent radical esophagectomy between January 2002 and December 2020 at the Wakayama Medical University Hospital. Statistical analyses were performed to evaluate risk factors for diaphragmatic hernia. Emergency surgery for postoperative diaphragmatic hernia was performed in nine of 622 patients (1.45%). Of these nine patients, one developed prolapse of the small intestine into the mediastinum (11.1%). The other eight patients underwent posterior mediastinal route reconstructions (88.9%), one of whom developed prolapse of the gastric conduit, and seven of whom developed transverse colon via the diaphragmatic hiatus. Laparoscopic surgery was identified in multivariate analysis as the only independent risk factor for diaphragmatic hernia (odd's ratio [OR] = 9.802, p = 0.034). In all seven cases of transverse colon prolapse into the thoracic cavity, the prolapsed organ had herniated from the left anterior part of gastric conduit. Laparoscopic surgery for esophageal cancer is a risk factor for diaphragmatic hernia. The left anterior surface of gastric conduit and diaphragmatic hiatus should be fixed firmly without compromising blood flow to the gastric conduit.

Radiographic duodenal invasion is associated with poor prognosis and early recurrence in patients with pancreatic ductal adenocarcinoma.

BACKGROUND: The prognostic impact of radiographic duodenal invasion (rDI) of pancreatic ductal adenocarcinoma (PDAC) has yet to be fully elucidated. This retrospective study aimed to investigate the prognostic and clinicopathological significance of rDI in patients with PDAC after pancreatoduodenectomy (PD). MATERIALS AND METHODS: We retrospectively analyzed 223 consecutive patients with resectable (R) and borderline resectable (BR)-PDAC that underwent up-front PD between 2002 and 2018. rDI was assessed by preoperative multi-detector row computed tomography. RESULTS: Ninety-three (42%) patients with PDAC had rDI, and all of them had pathological DI (pDI). The rDI(+) group had larger tumor size, BR-PDAC was more common, there was higher serum CA19-9 level, and microscopic lymphovascular invasion was more common than in the rDI(-) group. rDI was associated with significant reduction in overall survival (OS) (P < 0.001) and recurrence-free survival (RFS) (P < 0.001). In multivariate analysis, rDI was an independent prognostic factor in OS [hazard ratio (HR) = 0.52; 95% confidence interval (CI) 0.38-0.73, P < 0.001] and RFS [HR = 0.56; 95% CI 0.40-0.78, P = 0.001]. rDI was also an independent risk factor for early recurrence within 12 months [odds ratio (OR) = 0.36; 95% CI 0.18-0.73, P = 0.005]. rDI had positive correlation with liver recurrence (P = 0.024). CONCLUSION: Biological aggressiveness of PDAC with rDI implies short OS and early recurrence with frequent liver metastasis. Aggressive perioperative chemotherapy is recommended to improve prognosis, especially for R-PDAC patients with rDI.

Effects of the COVID-19 pandemic on gastroenterological surgeries in 2020: A study using the National Clinical Database of Japan.

Aim: This study aimed to investigate the effect of the coronavirus disease pandemic on the number of surgeries for gastroenterological cancer cases in Japan. Methods: The data recorded in the National Clinical Database of Japan between 2018 and 2020 were utilized for this study. Five specific surgeries for primary cancers and surgery for acute diffuse peritonitis were considered the primary endpoints. We divided the study period into the prepandemic and postpandemic (after April 2020) periods and examined the number of surgeries in relation to clinical factors. Results: Overall, 228 860 surgeries were analyzed. Among the five primary cancer surgeries, the number of distal gastrectomies for gastric cancer decreased the most (to 81.0% of the monthly number in the prepandemic period), followed by that of low anterior resections for rectal cancer (91.4%). In contrast, the number of pancreaticoduodenectomies for pancreatic cancer increased by 7.1%, while that of surgeries for peritonitis remained stable. This trend was observed nationwide. We also noted a marked reduction in the number of distal gastrectomy (to 72.5%), low anterior resection (84.0%), and esophagectomy (88.8%) procedures for T1 tumors. The noncurative resection rate and mortalities were low despite the increased proportion of T4 tumors and older patients. Conclusion: A marked reduction in surgeries for gastric and rectal cancers with early T factors may reflect prioritization of surgeries and reduction in cancer screenings. Although the quality of the surgery was maintained in terms of reduced mortalities and morbidities, the long-term effects of this pandemic should be monitored.

The degree of satisfaction and level of learning in male and female surgical residents: a nationwide questionnaire survey of graduating residents in Japan.

PURPOSE: Since 2002, the Japan Surgical Society has established a board certification system for surgeons to be certified for a specialty. Surgery remains a male-dominated field in Japan. This study aimed to clarify if the Japanese surgical residency training system is equally suitable for female and male residents. METHODS: The Japan Surgical Society conducted the first questionnaire survey regarding the system of surgical training for the residents in 2016. The questionnaire included the degree of satisfaction with 7 aspects of the training system, including the number and variety of cases experienced and duration and quality of instruction, and the learning level for 31 procedures. The degree of satisfaction and level of learning were compared between female and male residents. RESULTS: The degree of satisfaction was similar for all items between female and male residents. Female residents chose breast surgery as their subspecialty more frequently than male residents and were more confident in breast surgery procedures than male residents. Conversely, fewer female residents chose gastrointestinal surgery and were less confident in gastrointestinal surgery procedures than male residents. CONCLUSION: Female residents were as satisfied with the current surgical training system as male residents. However, there may be room for improvement in the surgical system, considering that fewer applications for gastrointestinal surgery come from female residents than from males.

Surgical Outcomes of Laparoscopic versus Open Hepatectomy for Left Hepatocellular Carcinoma: Propensity Score Analyses Using Retrospective Japanese and Korean Individual Patient Data.

Introduction: This study aimed to compare the prognostic impact of laparoscopic left hepatectomy (LLH) with that of open left hepatectomy (OLH) on patient survival after resection of left hepatocellular carcinoma (HCC). Methods: Among the 953 patients who received initial treatment for primary HCC that was resectable by either LLH or OLH from 2013 to 2017 in Japan and Korea, 146 patients underwent LLH and 807 underwent OLH. The inverse probability of treatment weighting approach based on propensity scoring was used to address the potential selection bias inherent in the recurrence and survival outcomes between the LLH and OLH groups. Results: The occurrence rate of postoperative complications and hepatic decompensation was significantly lower in the LLH group than in the OLH group. Recurrence-free survival (RFS) was better in the LLH group than in the OLH group (hazard ratio, 1.33; 95% confidence interval, 1.03-1.71; p = 0.029), whereas overall survival (OS) was not significantly different. Subgroup analyses of RFS and OS revealed an almost consistent trend in favor of LLH over OLH. In patients with tumor sizes of ≥4.0 cm or those with single tumors, both RFS and OS were significantly better in the LLH group than in the OLH group. Conclusions: LLH decreases the risk of tumor recurrence and improves OS in patients with primary HCC located in the left liver.

B cell receptor repertoire analysis from autopsy samples of COVID-19 patients.

Neutralizing antibodies against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are being developed world over. We investigated the possibility of producing artificial antibodies from the formalin fixation and paraffin-embedding (FFPE) lung lobes of a patient who died by coronavirus disease 2019 (COVID-19). The B-cell receptors repertoire in the lung tissue where SARS-CoV-2 was detected were considered to have highly sensitive virus-neutralizing activity, and artificial antibodies were produced by combining the most frequently detected heavy and light chains. Some neutralizing effects against the SARS-CoV-2 were observed, and mixing two different artificial antibodies had a higher tendency to suppress the virus. The neutralizing effects were similar to the immunoglobulin G obtained from healthy donors who had received a COVID-19 mRNA vaccine. Therefore, the use of FFPE lung tissue, which preserves the condition of direct virus sensitization, to generate artificial antibodies may be useful against future unknown infectious diseases.

Elective colorectal cancer surgery in nonagenarians and postoperative outcomes.

OBJECTIVES: The population of very elderly patients is increasing, and nonagenarians have significantly higher mortality rates and poorer rates of survival than younger patients. Meanwhile, recent studies have shown colorectal cancer surgery in nonagenarian patients to be feasible regarding postoperative outcomes. This retrospective study aims to evaluate the postoperative outcomes of nonagenarians in the latest clinical settings. METHODS: Consecutive nonagenarian patients who underwent elective colorectal cancer surgery between 2018 and 2020 retrospectively enrolled (Trial registration number: UMIN000046296 on December 7th, 2021). Clinicopathological data and short-term postoperative outcomes were collected for statistical analysis. RESULTS: This study included 81 nonagenarian patients (31 males, 50 females). Postoperative complications occurred in 21 patients (25.9%), and 3 patients died within 90 days (3.7%). Multivariate analysis revealed prognostic nutritional index was a significant predictor of postoperative complications (OR 2.99, 95% CI 0.78-9.10, P = 0.048), and performance status ≥ 3 could be an independent risk factor of 90-day mortality (HR 32.30, 95% CI 3.20-326.10, P = 0.032). CONCLUSIONS: Short-term outcomes after surgical treatment for nonagenarian patients with colorectal cancer were acceptable. Low prognostic nutritional index was closely related to postoperative complications and poor performance status could also lead to 90-day mortality. In aging populations, risk stratification to prevent poorer postoperative outcomes in nonagenarian patients is needed.

Induced pluripotent stem cell-derived dendritic cell vaccine therapy genetically modified on the ubiquitin-proteasome system.

We previously reported that dendritic cells (DCs) transduced with the full-length tumor-associated antigen (TAA) gene induced TAA-specific cytotoxic T lymphocytes (CTLs) to elicit antitumor responses. To overcome the issue of quantity and quality of DCs required for DC vaccine therapy, we focused on induced pluripotent stem cells (iPSCs) as a new tool for obtaining DCs and reported efficacy of iPSCs-derived DCs (iPSDCs). However, in clinical application of iPSDC vaccine therapy, further enhancement of the antitumor effect is necessary. In this study, we targeted mesothelin (MSLN) as a potentially useful TAA, and focused on the ubiquitin-proteasome system to enhance antigen-presenting ability of iPSDCs. The CTLs induced by iPSDCs transduced with MSLN gene (iPSDCs-MSLN) from healthy donors showed cytotoxic activity against autologous lymphoblastoid cells (LCLs) expressing MSLN (LCLs-MSLN). The CTLs induced by iPSDCs transduced ubiquitin-MSLN fusion gene exhibited higher cytotoxic activity against LCLs-MSLN than the CTLs induced by iPSDCs-MSLN. The current study was designed that peripheral T-cell tolerance to MSLN could be overcome by the immunization of genetically modified iPSDCs simultaneously expressing ubiquitin and MSLN, leading to a strong cytotoxicity against tumors endogenously expressing MSLN. Therefore, this strategy may be promising for clinical application as an effective cancer vaccine therapy.