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.

Type I interferon promotes the fate of Toll-like receptor 9-stimulated follicular B cells to plasma cell differentiation.

The activation and differentiation of B cells into plasma cells (PCs) play critical roles in the immune response to infections and autoimmune diseases. Toll-like receptor 9 (TLR9) responds to bacterial and viral DNA containing unmethylated CpG motifs and triggers immune responses in B cells; however, abnormal recognition of self-DNA by TLR9 can cause autoimmune diseases. When stimulated with TLR9 agonists, follicular (FO) B cells, a subset of B cells residing in the FO regions of secondary lymphoid organs, exhibit a propensity for activation but fail to give rise to PCs. The factors that enable the transition of TLR9-activated FO B cells from activation to differentiation into PCs remain unclear. In this study, we show that type I interferon-alpha (IFNα) signaling causes FO B cells activated by CpG stimulation to differentiate into PCs. Although CpG stimulation alone only temporarily increased interferon regulatory factor 4 (IRF4) expression in FO B cells, co-stimulation with both CpG and IFNα enhanced and maintained high IRF4 expression levels, ultimately enabling the cells to differentiate into PCs. Overexpression of IRF4 in FO B cells results in CpG-induced PC transition without IFN signaling. Furthermore, co-stimulation of TLR9 and IFNα receptors significantly enhanced mammalian target of rapamycin (mTOR) signaling, which regulates IRF4 expression and PC generation. These findings suggest that IFNα may play a key role in promoting the fate of PC differentiation in FO B cells activated by TLR9 stimulation.

Large-volume focus control at 10 MHz refresh rate via fast line-scanning amplitude-encoded scattering-assisted holography.

The capability of focus control has been central to optical technologies that require both high temporal and spatial resolutions. However, existing varifocal lens schemes are commonly limited to the response time on the microsecond timescale and share the fundamental trade-off between the response time and the tuning power. Here, we propose an ultrafast holographic focusing method enabled by translating the speed of a fast 1D beam scanner into the speed of the complex wavefront modulation of a relatively slow 2D spatial light modulator. Using a pair of a digital micromirror device and a resonant scanner, we demonstrate an unprecedented refresh rate of focus control of 31 MHz, which is more than 1,000 times faster than the switching rate of a digital micromirror device. We also show that multiple micrometer-sized focal spots can be independently addressed in a range of over 1 MHz within a large volume of 5 mm × 5 mm × 5.5 mm, validating the superior spatiotemporal characteristics of the proposed technique - high temporal and spatial precision, high tuning power, and random accessibility in a three-dimensional space. The demonstrated scheme offers a new route towards three-dimensional light manipulation in the 100 MHz regime.

A multi-institutional study designed by members of Tokyo Guidelines (TG) Core Meeting to elucidate the clinical characteristics and pathogenesis of acute cholangitis after bilioenteric anastomosis and biliary stent insertion with a focus on biliary obstruction: Role of transient hepatic attenuation difference (THAD) and pneumobilia in improving TG diagnostic performance.

BACKGROUND/PURPOSE: The aim of this study was to clarify the clinical characteristics of acute cholangitis (AC) after bilioenteric anastomosis and stent-related AC in a multi-institutional retrospective study, and validate the TG18 diagnostic performance for various type of cholangitis. METHODS: We retrospectively reviewed 1079 AC patients during 2020, at 16 Tokyo Guidelines 18 (TG 18) Core Meeting institutions. Of these, the post-biliary reconstruction associated AC (PBR-AC), stent-associated AC (S-AC) and common AC (C-AC) were 228, 307, and 544, respectively. The characteristics of each AC were compared, and the TG18 diagnostic performance of each was evaluated. RESULTS: The PBR-AC group showed significantly milder biliary stasis compared to the C-AC group. Using TG18 criteria, definitive diagnosis rate in the PBR-AC group was significantly lower than that in the C-AC group (59.6% vs. 79.6%, p < .001) because of significantly lower prevalence of TG 18 imaging findings and milder bile stasis. In the S-AC group, the bile stasis was also milder, but definitive-diagnostic rate was significantly higher (95.1%) compared to the C-AC group. The incidence of transient hepatic attenuation difference (THAD) and pneumobilia were more frequent in PBR-AC than that in C-AC. The definitive-diagnostic rate of PBR-AC (59.6%-78.1%) and total cohort (79.6%-85.3%) were significantly improved when newly adding these items to TG18 diagnostic imaging findings. CONCLUSIONS: The diagnostic rate of PBR-AC using TG18 is low, but adding THAD and pneumobilia to TG imaging criteria may improve TG diagnostic performance.

Gene Rearrangement and Expression of PRKACA and PRKACB Govern Morphobiology of Pancreatobiliary Oncocytic Neoplasms.

Intraductal oncocytic papillary neoplasms (IOPNs) are distinct from intraductal papillary mucinous neoplasms based on characteristic morphologic and genetic features represented by fusion genes involving PRKACA or PRKACB (PRKACA/B). However, pancreatic and biliary tumors with partial oncocytic features are often encountered clinically, and their molecular features are yet to be clarified. This study included 80 intraductal papillary neoplasms: 32 tumors with mature IOPN morphology (typical), 28 with partial or subclonal oncocytic features (atypical), and 20 without oncocytic features (control). We analyzed PRKACA/B fusion genes, including ATP1B1::PRKACA, DNAJB1::PRKACA, and ATP1B1::PRKACB, by reverse-transcription PCR; mRNA expression of fusion genes and nonrearranged PRKACA/B genes by quantitative reverse-transcription PCR; mutations in KRAS, BRAF, and GNAS by targeted sequencing or droplet digital PCR; and the expression of cyclic adenosine monophosphate (cAMP)-dependent protein kinase catalytic subunits α (PRKACA) and ß (PRKACB), phosphorylated cAMP response element-binding protein, and aberrations of p16, p53, SMAD4, STK11, and ß-catenin by immunohistochemistry. PRKACA/B fusion genes were detected in 100% (32/32) of typical, 46% (13/28) of atypical, and 0% (0/20) of control (P < .05). Expression of PRKACA, PRKACB, and phosphorylated cAMP response element-binding protein was upregulated in neoplasms with PRKACA/B fusion genes (P < .05). mRNA expression of the PRKACA/B fusion genes and protein expression of PRKACA or PRKACB tended to be higher in typical than in atypical cases (mRNA, P = .002; protein expression, P = .054). In some atypical neoplasms with mixed subtypes, PRKACA/B fusion genes were superimposed exclusively on oncocytic components. Typical IOPNs harbored fewer KRAS and GNAS mutations than control samples and fewer alterations in p53 and STK11 than atypical samples (P < .05). In conclusion, PRKACA/B fusion genes not only are the characteristic drivers of IOPNs but also play a crucial role in the development of subclonal oncocytic neoplasms. Moreover, oncocytic morphology is strongly associated with upregulation of PRKACA/B, which may provide clues for potential therapeutic options.

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.

Insights from managing clinical issues in distal pancreatectomy with en bloc coeliac axis resection: experiences from 626 patients.

BACKGROUND: Distal pancreatectomy with en bloc coeliac axis resection (DP-CAR) for pancreatic body cancer has been reported increasingly. However, its large-scale outcomes remain undocumented. This study aimed to evaluate DP-CAR volume and mortality, preoperative arterial embolization for ischaemic gastropathy, the oncological benefit for resectable tumours close to the bifurcation of the splenic artery and coeliac artery using propensity score matching, and prognostic factors in DP-CAR. METHODS: In a multi-institutional analysis, 626 DP-CARs were analysed retrospectively and compared with 1325 distal pancreatectomies undertaken in the same interval. RESULTS: Ninety-day mortality was observed in 7 of 21 high-volume centres (1 or more DP-CARs per year) and 1 of 41 low-volume centres (OR 20.00, 95 per cent c.i. 2.26 to 177.26). The incidence of ischaemic gastropathy was 19.2 per cent in the embolization group and 7.9 per cent in the no-embolization group (OR 2.77, 1.48 to 5.19). Propensity score matching analysis showed that median overall survival was 33.5 (95 per cent c.i. 27.4 to 42.0) months in the DP-CAR and 37.9 (32.8 to 53.3) months in the DP group. Multivariable analysis identified age at least 67 years (HR 1.40, 95 per cent c.i. 1.12 to 1.75), preoperative tumour size 30 mm or more (HR 1.42, 1.12 to 1.80), and preoperative carbohydrate antigen 19-9 level over 37 units/ml (HR 1.43, 1.11 to 1.83) as adverse prognostic factors. CONCLUSION: DP-CAR can be performed safely in centres for general pancreatic surgery regardless of DP-CAR volume, and preoperative embolization may not be required. This procedure has no oncological advantage for resectable tumour close to the bifurcation of the splenic artery, and should be performed after appropriate patient selection.

Standard versus delayed initiation of S-1 adjuvant chemotherapy after surgery for pancreatic cancer: a secondary analysis of a nationwide cohort by the Japan Pancreas Society.

BACKGROUND: Based on the Japan Adjuvant Study Group of Pancreatic Cancer-01 results, S-1 adjuvant chemotherapy has been the standard in resected pancreatic ductal adenocarcinoma (PDAC) patients in Japan and elsewhere, initiated within 10 weeks after surgery. To assess the clinical impact of this timing, we conducted a secondary analysis of a nationwide survey by the Japan Pancreas Society. METHODS: A total of 3361 patients were divided into two groups: 2681 (79.8%) initiating the therapy within 10 weeks after surgery (standard) and 680 (20.2%) after 10 weeks (delayed). We compared recurrence-free survival (RFS) and overall survival (OS) using the log-rank test and Cox proportional hazards model with conditional landmark analysis between the groups. Results were verified by adjustment with inverse-probability-of-treatment weighting (IPTW) analysis. RESULTS: The median timing of S-1 adjuvant chemotherapy initiation was 50 days (interquartile range: 38-66). In the standard group, 5-year RFS and OS rates were 32.3-48.7%, respectively, compared with 25.0-38.7% in the delayed group. Hazard ratios (HRs) and 95% confidence intervals were 0.84 (0.76-0.93) for RFS (p < 0.001) and 0.77 (0.69-0.87) for OS (p < 0.001). The IPTW analysis yielded 5-year RFS rates of 32.1% and 25.3% in the standard versus delayed group, respectively [HR = 0.86 (0.77-0.96), p < 0.001] and 5-year OS rates of 48.3% and 39.8%, respectively [HR = 0.81 (0.71-0.92), p < 0.001]. CONCLUSIONS: Initiation of S-1 adjuvant chemotherapy in resected PDAC patients within 10 weeks after surgery may offer survival benefit over later initiation.

Impact of S-1 adjuvant chemotherapy longer than 6 months on survival in patients with resected pancreatic cancer: a nationwide survey by the Japan Pancreas Society based on real-world data.

BACKGROUND: Based on the Japan Adjuvant Study Group of Pancreatic Cancer 01 study, the standard duration of adjuvant chemotherapy with S-1 (an oral 5-fluorouracil prodrug consisting of tegafur, gimeracil, and oteracil) in patients with resected pancreatic ductal adenocarcinoma (PDAC) was considered to be 6 months, but the impact of increasing its duration on postoperative survival was unknown. Here, the authors investigated this question by reviewing real-world data from a large cohort of patients with PDAC. METHODS: In total, 3949 patients who underwent surgery for PDAC during the study period followed by S-1 adjuvant chemotherapy in board-certified institutions were included. Based on the duration of S-1 chemotherapy, two subgroups were defined: a standard-duration group that included patients who were treated for 180 ± 30 days and a longer duration group that included patients who received treatment for >210 days. RESULTS: The median duration of S-1 chemotherapy was 167 days, with a mean ± standard deviation of 200 ± 193 days. After excluding patients who had a recurrence within 210 days after the initiation of adjuvant chemotherapy, postoperative recurrence-free survival (RFS) and overall survival (OS) in the standard-duration group (n = 1473) and the longer duration group (n = 975) were compared. RFS and OS did not differ significantly between the standard-duration and longer duration groups (5-year RFS: 37.8% vs. 36.2% respectively; p = .6186; 5-year OS: 52.8% vs. 53.4%, respectively; p = .5850). The insignificant difference was verified by multivariate analysis and propensity-score matching analysis. CONCLUSIONS: The current findings suggest that extending S-1 adjuvant chemotherapy beyond 6 months has no significant additional effect on survival in patients with PDAC. This could be useful in determining whether to extend S-1 chemotherapy in patients who have completed the standard 6-month treatment.

Serine/Threonine Kinase 11 Plays a Canonical Role in Malignant Progression of KRAS -Mutant and GNAS -Wild-Type Intraductal Papillary Mucinous Neoplasms of the Pancreas.

OBJECTIVE: We aimed to elucidate the clinicopathobiological significance of Serine/Threonine Kinase 11 (STK11) in pancreatic intraductal papillary mucinous neoplasms (IPMNs). BACKGROUND: STK11 is a tumor suppressor involved in certain IPMNs; however, its significance is not well known. METHODS: In 184 IPMNs without Peutz-Jeghers syndrome, we analyzed expression of STK11 and phosphorylated-AMPKa in all cases, and p16, p53, SMAD4, and ß-catenin in 140 cases by immunohistochemistry; and we analyzed mutations in 37 genes, including whole coding exons of STK11, CDKN2A, TP53, and SMAD4, and hotspots of KRAS, BRAF, and GNAS in 64 cases by targeted sequencing. KRAS and GNAS were additionally analyzed in 86 STK11-normal IPMNs using digital-PCR. RESULTS: Consistent loss or reduction of STK11 expression was observed in 26 of 184 (14%) IPMNs. These STK11-aberrant IPMNs were 17 of 45 (38%) pancreatobiliary, 8 of 27 (30%) oncocytic, 1 of 54 (2%) gastric, and 0 of 58 (0%) intestinal subtypes ( P = 8.5E-11), and 20 of 66 (30%) invasive, 6 of 74 (8%) high-grade, and 0 of 44 (0%) low-grade ( P = 3.9E-06). Sixteen somatic STK11 mutations (5 frameshift, 6 nonsense, 1 splicing, and 4 missense) were detected in 15/26 STK11-aberrant IPMNs ( P = 4.1E-06). All STK11-aberrantIPMNs were GNAS -wild-type and 96% of them were KRAS or BRAF -mutant.Morphologically, STK11-aberrant IPMNs presented "fern-like" arborizing papillae with thin fibrovascular core. Phosphorylated-AMPKa was down-regulated in STK11-aberrant IPMNs (92%, P = 6.8E-11). Patients with STK11-aberrant IPMNs showed poorer survival than patients with STK11-normal IPMNs ( P = 3.6E-04 overall; P = 6.1E-04 disease-free). CONCLUSION: STK11 may play a canonical role in malignant progression and poor survival of patients with IPMNs. Aberrant STK11-driven phosphorylated AMPK downregulation may provide therapeutic opportunities with mTOR inhibitors/AMPK activators.

Clinical practice guidelines for duodenal cancer 2021.

Duodenal cancer is considered to be a small intestinal carcinoma in terms of clinicopathology. In Japan, there are no established treatment guidelines based on sufficient scientific evidence; therefore, in daily clinical practice, treatment is based on the experience of individual physicians. However, with advances in diagnostic modalities, it is anticipated that opportunities for its detection will increase in future. We developed guidelines for duodenal cancer because this disease is considered to have a high medical need from both healthcare providers and patients for appropriate management. These guidelines were developed for use in actual clinical practice for patients suspected of having non-ampullary duodenal epithelial malignancy and for patients diagnosed with non-ampullary duodenal epithelial malignancy. In this study, a practice algorithm was developed in accordance with the Minds Practice Guideline Development Manual 2017, and Clinical Questions were set for each area of epidemiology and diagnosis, endoscopic treatment, surgical treatment, and chemotherapy. A draft recommendation was developed through a literature search and systematic review, followed by a vote on the recommendations. We made decisions based on actual clinical practice such that the level of evidence would not be the sole determinant of the recommendation. This guideline is the most standard guideline as of the time of preparation. It is important to decide how to handle each case in consultation with patients and their family, the treating physician, and other medical personnel, considering the actual situation at the facility (and the characteristics of the patient).

JPN clinical practice guidelines 2021 with easy-to-understand explanations for the management of acute pancreatitis.

BACKGROUND: In preparing the Japanese (JPN) guidelines for the management of acute pancreatitis 2021, the committee focused the issues raised by the results of nationwide epidemiological survey in 2016 in Japan. METHOD: In addition to a systematic search using the previous JPN guidelines, papers published from January 2014 to September 2019 were searched for the contents to be covered by the guidelines based on the concept of GRADE system. RESULTS: Thirty-six clinical questions (CQ) were prepared in 15 subject areas. Based on the facts that patients diagnosed with severe disease by both Japanese prognostic factor score and contrast-enhanced computed tomography (CT) grade had a high fatality rate and that little prognosis improvement after 2 weeks of disease onset was not obtained, we emphasized the importance of Pancreatitis Bundles, which were shown to be effective in improving prognosis, and the CQ sections for local pancreatic complications had been expanded to ensure adoption of a step-up approach. Furthermore, on the facts that enteral nutrition for severe acute pancreatitis was not started early within 48 h of admission and that unnecessary prophylactic antibiotics was used in almost all cases, we emphasized early enteral nutrition in small amounts even if gastric feeding is used and no prophylactic antibiotics are administered in mild pancreatitis. CONCLUSION: All the members of the committee have put a lot of effort into preparing the extensively revised guidelines in the hope that more people will have a common understanding and that better medical care will be spread.

Intrahepatic Cholangiocarcinoma With Neither Intrahepatic Metastasis Nor Lymph Node Metastasis Is the Optimal Indication for Hepatectomy With Adjuvant Therapy.

Background/Aim: The optimal indication of hepatectomy with adjuvant therapy for intrahepatic cholangiocarcinoma (ICC) has not been evaluated in detail. Patients and Methods: We retrospectively studied 224 patients with ICC who underwent hepatectomy between 2000 and 2019. Prognostic factors for overall survival (OS) were evaluated by univariate and multivariate analysis. A total of 127 patients were treated with adjuvant therapy (62 patients with chemotherapy and 65 patients with immunotherapy) after hepatectomy, and 97 patients were treated with hepatectomy alone. Results: Intrahepatic metastasis (IM), lymph node metastasis (LNM) of ICC, adjuvant chemotherapy, and adjuvant immunotherapy were significant prognostic factors for OS on multivariate analysis. In 127 patients with neither IM nor LNM, the 5-year OS rate was significantly higher in 36 patients with adjuvant chemotherapy (81%) and in 34 patients with adjuvant immunotherapy (68%) than in 57 patients with hepatectomy alone (45%). Conclusion: The absence of IM or LNM is the optimal indication for hepatectomy with adjuvant therapy in patients with ICC.

Evaluation of the Significance of Lymphatic, Microvascular and Perineural Invasion in Patients With Pancreatic Neuroendocrine Neoplasms.

Background: Some prognostic factors for pancreatic neuroendocrine neoplasms (PanNENs) have been reported; however, the significance of lymphatic, microvascular, and perineural invasion remains unclear. We aimed to clarify the role of these factors in PanNEN recurrence. Patients and Methods: We analyzed 138 patients who underwent curative pancreatectomy and were pathologically diagnosed with PanNEN. We evaluated the association between clinicopathological factors and the recurrence of PanNENs. Results: The numbers of patients with lymphatic, microvascular, and perineural invasion were 34 (25%), 43 (31%) and 17 (12%), respectively. Twenty-four patients (17%) had recurrences, and the 3, 5, and 10-year recurrence-free survival (RFS) rates were 88%, 84%, and 76%, respectively. The recurrence sites (with duplication) were mainly the liver (twenty-two patients), followed by the lymph nodes (seven patients), and bone (two patients). In multivariate analyses, grade 2-3 and the presence of microvascular invasion were significant risk factors for RFS (hazard ratio=7.5 and 7.9, respectively). When examining outcomes according to these factors, the 5-year RFS rates of patients with risk scores of 0, 1, and 2 were 100%, 91%, and 32%, respectively (p<0.001). Even in patients with grade 1 (n=97) or limited resection (enucleation, splenic-preserving distal pancreatectomy, central pancreatectomy, and duodenum-preserving pancreatic head resection, n=62), the presence of microvascular invasion was a significant risk factor for RFS (hazard ratio=13.4 and 18.0, respectively). Conclusion: The presence of microvascular invasion is an independent risk factor for recurrence in patients with PanNEN.

Examination of the characteristics of long-term survivors among patients with gallbladder cancer with liver metastasis who underwent surgical treatment: a retrospective multicenter study (ACRoS1406).

BACKGROUND: Gallbladder cancer (GBC) with liver metastasis is considered unresectable. However, there have been infrequent reports of long-term survival in patients with GBC and liver metastases. Therefore, we examined the characteristics of long-term survivors of gallbladder cancer with liver metastasis. METHODS: A retrospective multicenter study of 462 patients with GBC (mean age, 71 years; female, 51%) was performed. Although patients with pre-operatively diagnosed GBC and liver metastasis were generally excluded from resection, some cases identified during surgery were resected. RESULT: In patients with resected stage III/IV GBC (n = 193), the period 2007-2013 (vs. 2000-2006, hazard ratio 0.63), pre-operative jaundice (hazard ratio 1.70), ≥ 2 liver metastases (vs. no liver metastasis, hazard ratio 2.11), and metastasis to the peritoneum (vs. no peritoneal metastasis, hazard ratio 2.08) were independent prognostic factors for overall survival, whereas one liver metastasis (vs. no liver metastasis) was not. When examining the 5-year overall survival and median survival times by liver metastasis in patients without peritoneal metastasis or pre-operative jaundice, those with one liver metastasis (63.5%, not reached) were comparable to those without liver metastasis (40.4%, 33.0 months), and was better than those with ≥ 2 liver metastases although there was no statistical difference (16.7%, 9.0 months). According to the univariate analysis of resected patients with GBC and liver metastases (n = 26), minor hepatectomy, less blood loss, less surgery time, papillary adenocarcinoma, and T2 were significantly associated with longer survival. Morbidity of Clavien-Dindo classification ≤ 2 and received adjuvant chemotherapy were marginally not significant. Long-term survivors (n = 5) had a high frequency of T2 tumors (4/5), had small liver metastases near the gallbladder during or after surgery, underwent minor hepatectomy without postoperative complications, and received postoperative adjuvant chemotherapy. CONCLUSIONS: Although there is no surgical indication for GBC with liver metastasis diagnosed pre-operatively, minor hepatectomy and postoperative chemotherapy may be an option for selected patients with T2 GBC and liver metastasis identified during or after surgery who do not have other poor prognostic factors.

Postoperative Treatment of Resectable Pancreatic Cancer With Positive Peritoneal Lavage Cytology: A Multicentre Retrospective Study.

BACKGROUND/AIM: We aimed to evaluate pancreatic cancer (PC) with positive peritoneal lavage cytology (CY1) outcomes following a change in adjuvant therapy. PATIENTS AND METHODS: The clinicopathological data of patients with pancreatic adenocarcinoma with CY1 at 14 institutions, between 2007 and 2015, were collected and analyzed. RESULTS: Of the 124 eligible patients, 114 underwent macroscopically curative resection. Of the 114 patients, 80 (70%) did not have early recurrence and received postoperative chemotherapy that was S-1 in 43 (54%), gemcitabine in 31 (39%), and others in six (7%). The median overall survival was 21.0 months in S-1 and 19.2 in gemcitabine therapy (p=0.23), whereas the median relapse-free survival was 10.2 and 7.1 months (p=0.03), respectively. CONCLUSION: Following the change in adjuvant therapy, most PC patients with CY1 who underwent macroscopically curative resection received S-1; however, it was insufficient. Further development of postoperative chemotherapy is required.

Surgical results of non-ampullary duodenal cancer: a nationwide survey in Japan.

BACKGROUND: As non-ampullary duodenal cancer is relatively rare, the optimal treatment strategy, including the appropriate surgical procedure and efficacy of adjuvant chemotherapy, remains unclear. This nationwide survey aimed to clarify the actual lymph node spread pattern and determine the optimal treatment strategy for this disease, using a large-scale database. METHODS: We used a questionnaire and a retrospective registry of 1083 patients with non-ampullary duodenal cancer who had undergone surgery during 2008-2017 in 114 high-volume Japanese Society of Hepatobiliary and Pancreatic Surgery-certified training institutions. Propensity score-matched analyses were conducted to minimise background bias. Cox regression was performed to identify covariates associated with recurrence-free survival. There were distinct disparities in the nodal dissection rate according to the predominant tumor location and tumor invasion depth. Metastases were frequently observed in the peripancreatic nodes and those along the superior mesenteric artery, irrespective of tumor location. Their dissection seemed to be beneficial for improved survival. In the overall cohort, no survival benefit was observed in patients who received adjuvant chemotherapy when compared with that in patients who underwent surgery alone. Nevertheless, in the matched cohort, adjuvant chemotherapy for > 6 months was associated with a significant improvement in recurrence-free survival (median: 43.5 vs. 22.5 months, p = 0.016), particularly in patients with tumor invasion of the subserosa or deeper tumor invasion, lymph node metastasis, or elevated serum carbohydrate antigen 19-9 levels. CONCLUSION: Pancreatoduodenectomy should be the standard procedure for advanced non-ampullary duodenal cancer. Adjuvant chemotherapy for > 6 months, especially for advanced tumors, significantly improves survival.

A case of pathologically complete response after preoperative chemotherapy in a pancreatic acinar cell carcinoma patient with portal vein tumor thrombosis.

Preoperative treatment is being proposed as a standard treatment for pancreatic ductal adenocarcinoma though few cases show a pathologically complete response. On the other hand, there is no consensus regarding preoperative chemotherapy for pancreatic acinar cell carcinoma (ACC). The present study described a rare case of ACC in the pancreatic head with portal vein tumor thrombosis (PVTT) treated with preoperative chemotherapy using modified FOLFIRINOX, which achieved a pathologically complete response. A 65-year-old man was referred for consideration of treatment strategy. Contrast-enhanced abdominal computed tomography revealed a pancreatic tumor and PVTT. The pancreatic tumor was diagnosed as ACC by an endoscopic ultrasound-guided fine-needle aspiration biopsy. Initially, the tumor was assessed as unresectable due to the presence of PVTT, and therefore, a chemotherapy using modified FOLFIRINOX was administered. After 14 courses of the chemotherapy, imaging studies revealed that the tumor and PVTT showed marked reduction in size; thus, the patient underwent pancreaticoduodenectomy with combined resection of the portal vein (PV). A pathological examination uncovered a complete degeneration of the primary tumor and the PV embolus without any residue of carcinoma. The patient did not receive adjuvant chemotherapy and survived with no evidence of recurrence for 33 months after surgery. The chemotherapy using modified FOLFIRINOX could give a complete response in patients with pancreatic ACC with PVTT.

Whole-exome Sequencing Reveals New Potential Susceptibility Genes for Japanese Familial Pancreatic Cancer.

OBJECTIVE: The primary objective of this study was to identify novel genes that predispose people in the Japanese population to FPC. SUMMARY OF BACKGROUND DATA: Familial history of pancreatic cancer is an important risk factor but, to date, few genes predisposing individuals to increased risk of developing FPC have been identified. METHODS: We performed whole-exome sequencing of germline DNA from 81 Japanese FPC patients. We also investigated somatic gene alterations in 21 matched tumor tissues through whole-exome sequencing and copy number analysis. RESULTS: Our germline variants identified previously known FPC susceptibility genes such as ATM and BRCA2, and several novel tumor suppressor genes with potentially deleterious variants for FPC. Interestingly, somatic whole-exome analysis demonstrated that most tumor samples with suspicious loss of heterozygosity of candidate genes were KRAS wild-types, implying that these cases may not have required KRAS activation as a driver event for carcinogenesis. CONCLUSIONS: Our findings indicate that FPC patients harbor potentially deleterious causative germline variants in tumor suppressor genes, which are known to acquire somatic mutations in pancreatic cancer, and that somatic loss of heterozygosity of some FPC susceptibility genes may contribute to the development of FPC in the absence of somatic KRAS-activating mutation. Genetic testing for a wider variety of FPC-predisposition genes could provide better screening approach for high-risk groups of pancreatic cancer.

International Expert Consensus on Precision Anatomy for minimally invasive distal pancreatectomy: PAM-HBP Surgery Project.

BACKGROUND: Surgical views with high resolution and magnification have enabled us to recognize the precise anatomical structures that can be used as landmarks during minimally invasive distal pancreatectomy (MIDP). This study aimed to validate the usefulness of anatomy-based approaches for MIDP before and during the Expert Consensus Meeting: Precision Anatomy for Minimally Invasive HBP Surgery (February 24, 2021). METHODS: Twenty-five international MIDP experts developed clinical questions regarding surgical anatomy and approaches for MIDP. Studies identified via a comprehensive literature search were classified using Scottish Intercollegiate Guidelines Network methodology. Online Delphi voting was conducted after experts had drafted the recommendations, with the goal of obtaining >75% consensus. Experts discussed the revised recommendations in front of the validation committee and an international audience of 384 attendees. Finalized recommendations were made after a second round of online Delphi voting. RESULTS: Four clinical questions were addressed, resulting in 10 recommendations. All recommendations reached at least a 75% consensus among experts. CONCLUSIONS: The expert consensus on precision anatomy for MIDP has been presented as a set of recommendations based on available evidence and expert opinions. These recommendations should guide experts and trainees in performing safe MIDP and foster its appropriate dissemination worldwide.