Clonal analysis of metachronous double biliary tract cancers

The molecular mechanisms underpinning the development of metachronous tumors in the remnant bile duct following surgical resection of primary biliary tract carcinomas (BTCs) are unknown. This study aimed to elucidate these mechanisms by evaluating the clinicopathologic features of BTCs, the alterations to 31 BTC-related genes on targeted sequencing, and the aberrant expression of p53, p16, SMAD4, ARID1A and β-catenin on immunohistochemistry. Twelve consecutive patients who underwent resection of metachronous BTCs following primary BTC resection with negative bile duct margins were enrolled. Among the 12 metachronous tumors, six exhibited anterograde growth in the lower portion and six exhibited retrograde growth in the upper portion of the biliary tree. Surgical resection of metachronous BTCs resulted in recurrence-free survival in seven, local recurrence in five, and death in two patients. Nine achieved 5-year overall survival after primary surgery. Molecular analyses revealed that recurrently altered genes were: TP53, SMAD4, CDKN2A, ELF3, ARID1A, GNAS, NF1, STK11, RNF43, KMT2D and ERBB3. Each of these was altered in at least three cases. A comparison of the molecular features between 12 paired primary and metachronous BTCs indicated that 10 (83%) metachronous tumors developed in clonal association with corresponding primary tumors either successionally or phylogenically. The remaining two (17%) developed distinctly. The successional tumors consisted of direct or evolved primary tumor clones that spread along the bile duct. The phylogenic tumors consisted of genetically unstable clones and conferred a poor prognosis. Metachronous tumors distinct from their primaries harbored fewer mutations than successional and phylogenic tumors. In conclusion, over 80% of metachronous BTCs that develop following primary BTC resection are probably molecularly associated with their primaries in either a successional or a phylogenetic manner. Comparison between the molecular features of a metachronous tumor and those of a preceding tumor may provide effective therapeutic clues for the treatment of metachronous BTC. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

The Significance of Bile in the Biliopancreatic Limb on Metabolic Improvement After Duodenal-Jejunal Bypass

INTRODUCTION

Duodenal-jejunal bypass (DJB) is an experimental procedure in metabolic surgery that does not have a restrictive component. Changes in bile acid (BA) dynamics and intestinal microbiota are possibly related to metabolic improvement after DJB. Our previous studies involving obese diabetic rats showed the crucial role of the biliopancreatic limb (BPL) in metabolic improvement after DJB caused by BA reabsorption. We established a new DJB procedure to prevent bile from flowing into the BPL and aimed to elucidate the importance of bile in the BPL after DJB.

METHODS

Otsuka Long-Evans Tokushima Fatty rats with diabetes were divided into three groups: two DJB groups and a sham group (n = 11). Duodenal-jejunal anastomosis was performed proximal to the papilla of Vater in the DJB group (n = 11). However, the DJB-D group (n = 11) underwent a new procedure with duodenal-jejunal anastomosis distal to the papilla of Vater for preventing bile flow into the BPL.

RESULTS

Glucose metabolism improved and weight gain was suppressed in the DJB group, but not in the DJB-D and sham groups. Serum BA level and conjugated BA concentration were elevated in the DJB group. The gut microbiota was altered only in the DJB group; the abundance of Firmicutes and Bacteroidetes decreased and that of Actinobacteria increased. However, the DJB-D group exhibited no apparent change in the gut microbiota, similar to the sham group.

CONCLUSION

BAs are essential in the BPL for metabolic improvement after DJB; they can improve the gut microbiota in these processes.

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 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 WHO 2019 classification. Overall, 1,490 patients met the eligibility criteria, and 1,014 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.

A case report of perihilar cholangiocarcinoma in a patient with situs inversus totalis

Situs inversus totalis is a rare congenital malformation in which organs are positioned in a mirror-image relationship to normal conditions. It often presents with vascular and biliary malformations. Only a few reports have pointed out the surgical difficulties in patients with situs inversus totalis, especially in those with perihilar cholangiocarcinoma. This report describes a 66-year-old male patient who underwent left hemihepatectomy (S5, 6, 7, and 8) with combined resection of the caudate lobe (S1), extrahepatic bile duct, and regional lymph nodes for perihilar cholangiocarcinoma with situs inversus totalis. Cholangiocarcinoma was mainly located in the perihilar area and progressed extensively into the bile duct. Surgery was performed after careful evaluation of the unusual anatomy. Although several vascular anomalies required delicate manipulation, the procedures were performed without major intraoperative complications. Postoperatively, bile leakage occurred, but the patient recovered with drainage treatment. The patient was discharged on the 29th postoperative day. Adjuvant chemotherapy with S-1 was administered for approximately 6 months. There was no recurrence 15 months postoperatively. Appropriate imaging studies and an understanding of unusual anatomy make surgery safe and provide suitable treatment for patients with situs inversus totalis.

Downregulation of ABCC3 activates MAPK signaling through accumulation of deoxycholic acid in colorectal cancer cells

ABCC3 (also known as MRP3) is an ATP binding cassette transporter for bile acids, whose expression is downregulated in colorectal cancer through the Wnt/β-catenin signaling pathway. However, it remained unclear how downregulation of ABCC3 expression contributes to colorectal carcinogenesis. We explored the role of ABCC3 in the progression of colorectal cancer-in particular, focusing on the regulation of bile acid export. Gene expression analysis of colorectal adenoma isolated from familial adenomatous polyposis patients revealed that genes related to bile acid secretion including ABCC3 were downregulated as early as at the stage of adenoma formation. Knockdown or overexpression of ABCC3 increased or decreased intracellular concentration of deoxycholic acid, a secondary bile acid, respectively, in colorectal cancer cells. Forced expression of ABCC3 suppressed deoxycholic acid-induced activation of MAPK signaling. Finally, we found that nonsteroidal anti-inflammatory drugs increased ABCC3 expression in colorectal cancer cells, suggesting that ABCC3 could be one of the targets for therapeutic intervention of familial adenomatous polyposis. Our data thus suggest that downregulation of ABCC3 expression contributes to colorectal carcinogenesis through the regulation of intracellular accumulation of bile acids and activity of MAPK signaling.

Histopathological analysis of tumor microenvironment in adrenocortical carcinoma: Possible effects of in situ disorganized glucocorticoid production on tumor immunity

Adrenocortical carcinoma (ACC) patients with glucocorticoid excess have been reported to be associated with decreased tumor-infiltrating immune cells, but the effects of in situ glucocorticoid production on tumor immunity have remained unknown. In addition, ACC was also known to harbor marked intra-tumoral heterogeneity of steroidogenesis or disorganized steroidogenesis. Therefore, in this study, we immune-profiled tumor-infiltrating lymphocytes (TILs) and tumor-associated macrophages (TAMs) and pivotal steroidogenic enzymes of glucocorticoid biosynthesis (CYP17A and CYP11B1) to explore the potential effects of in situ glucocorticoid production and intra-tumoral heterogeneity/disorganized steroidogenesis on tumor immunity of ACC. We also studied the correlations of the status of tumor immunity with that of angiogenesis and tumor grade to further explore the tumor tissue microenvironment of ACC. TILs (CD3, CD4, CD8, and FOXP3), TAMs (CD68 and CD163), key steroidogenic enzymes of glucocorticoid (CYP17A and CYP11B1), angiogenesis (CD31 and vasohibin-1 (VASH-1)), tumor grade (Ki-67 and Weiss score) were immunohistochemically evaluated in 34 ACCs. Increased CYP17A immunoreactivity in the whole tumor area was significantly positively correlated with FOXP3-positive TILs (p = 0.021) and negatively with CD4/CD3 ratio (p = 0.001). Increased CYP11B1 immunoreactivity in the whole tumor area was significantly positively correlated with CD8/CD3 (p = 0.039) and CD163/CD68 ratios (p = 0.006) and negatively with CD4-positive TILs (p = 0.036) and CD4/CD3 ratio (p = 0.001). There were also significant positive correlations between CYP17A and CD8 (r = 0.334, p < 0.001) and FOXP3-positive TILs (r = 0.414, p < 0.001), CD8/CD3 ratio (r = 0.421, p < 0.001), and CD68-positive TAMs (r = 0.298, p < 0.001) in randomly selected areas. Significant positive correlations were also detected between CYP11B1 and CD8/CD3 ratio (r = 0.276, p = 0.001) and negative ones detected between CYP11B1 and CD3- (r = -0.259, p = 0.002) and CD4-positive TILs (r = -0.312, p < 0.001) in those areas above. Increased micro-vessel density (MVD) -VASH-1 was significantly positively correlated with CD68- (p = 0.015) and CD163-positive TAMs (p = 0.009) and CD163/CD68 ratio and the high VASH-1 with CD163-positive TAMs (p = 0.042). Ki-67 labeling index was significantly positively correlated with MAD-VASH-1 (p = 0.006) and VASH-1 (p = 0.006) status. Results of our present study indicated that in situ glucocorticoid production did influence the status of tumor immunity in ACC. In particular, increased levels of CYP17A and CYP11B1, both involved in glucocorticoid producing immunoreactivity played different effects on tumor immunity, i.e., reflecting the involvement of intra-tumoral heterogeneity and disorganized steroidogenesis of ACC, which also did indicate the importance of in situ approaches when analyzing tumor immunity of ACC.

Revascularization and Digestive Tract Repair in Secondary Aortoenteric Fistula Using a Single-Center in Situ Revascularization Strategy

BACKGROUND

Information regarding optimal revascularization and digestive tract repair in secondary aortoenteric fistula (sAEF) remains unclear. Thus, reporting treatment outcomes and presenting comprehensive patient details through a structured treatment approach are necessary to establish a treatment strategy for this rare, complex, and fatal condition.

METHODS

We performed a single-center retrospective review of consecutive sAEF managed based on our in situ revascularization and intestinal repair strategy. The primary endpoint of this study was all-cause mortality, and secondary endpoints were the incidence of in-hospital complications and midterm reinfections.

RESULTS

Between 2007 and 2020, 16 patients with sAEF, including 13 men (81%), underwent in situ revascularization and digestive tract repair. The median follow-up duration for all participants was 36 (interquartile range, 6-62) months. Among the participants, 81% (n = 13), 13% (n = 2), and 6% (n = 1) underwent aortic reconstruction with rifampin-soaked grafts, unsoaked Dacron grafts, and femoral veins, respectively. The duodenum was the most commonly involved site in enteric pathology (88%; n = 14), and 57% (n = 8) of duodenal breaks were repaired by a simple closure. Duodenum's second part-jejunum anastomosis was performed in 43% of patients (n = 6), and 19% of the patients (n = 3) died perioperatively. In-hospital complications occurred in 88% patients (n = 14), and the most frequent complication was gastrointestinal. Finally, 81% patients (n = 13) were discharged home. Oral antibiotics were administered for a median duration of 5.7 months postoperatively; subsequently, the participants were followed up carefully. Reinfection was detected in 6% of the patients (n = 1) who underwent reoperation without any complications. The 1-year and 3-year overall survival rates of participants were 75% (n = 12) and 75% (n = 9), respectively, and no sAEF-related deaths occurred, except perioperative death.

CONCLUSIONS

Surgical intervention with contemporary management based on our vascular strategy and digestive tract procedure may be a durable treatment for sAEF.

Rupture of ectopic varices of the ascending colon occurring after pancreatic cancer surgery: A case report and literature review

A 69-year-old woman, a long-term survivor of subtotal stomach-preserving pancreatoduodenectomy with the splenic vein resection for pancreatic cancer, visited our hospital with a chief complaint of bloody stools. Previously, she was diagnosed with varices in the ascending colon due to left-sided portal hypertension after pancreatoduodenectomy by computed tomography and colonoscopy. After emergency hospitalization, she went into shock, and blood tests showed acute progression of severe anemia. Computed tomography showed a mosaic-like fluid accumulation from the ascending colon to the rectum. She was diagnosed with ruptured varices in the ascending colon. Emergency colonoscopy was performed, and treatment with endoscopic injection sclerotherapy using N-butyl-2-cyanoacrylate was successful. Ectopic varices occur at any location other than the esophagus and stomach, and colonic varices are rare among them. They are mostly caused by portal hypertension due to liver cirrhosis. However, with the trend of improving the prognosis for patients with pancreatic cancer, we should occasionally pay attention to the development of ectopic varices including colonic varices in patients who have undergone pancreatoduodenectomy with superior mesenteric and splenic veins resection. Treatment methods for colonic varices varied from case to case, including conservative therapy, interventional radiology, and endoscopic procedure. In this case, endoscopic injection sclerotherapy was successfully performed without any complications. To the best of our knowledge, this is the first study to report successful treatment with endoscopic injection sclerotherapy for varices in the ascending colon caused by left-sided portal hypertension after pancreatoduodenectomy. Colonic varices should be considered in patients with obscure gastrointestinal bleeding after pancreatoduodenectomy.

A Recombinant Peptide Device Combined with Adipose Tissue-Derived Stem Cells Enhances Subcutaneous Islet Engraftment

Subcutaneous space has been considered an attractive site for islet graft transplantation; however, the oxygen tension and vascularization are insufficient for islet graft survival. We investigated whether subcutaneous pre-implantation of a recombinant peptide (RCP) device with adipose tissue-derived stem cells (ADSCs) enhanced subcutaneous islet engraftment. RCP devices with/without syngeneic ADSCs were pre-implanted into the subcutaneous space of C57BL/6 mice. Syngeneic islets (300 or 120 islet equivalents (IEQs)) were transplanted into the pre-treated space after diabetes induction using streptozotocin. The cure rates of groups in which RCP devices were implanted four weeks before transplantation were significantly better than the intraportal transplantation group when 300 IEQs of islets were transplanted (p < 0.01). The blood glucose changes in the RCP+ADSCs-4w group was significantly ameliorated in comparison to the RCP-4w group when 120 IEQs of islets were transplanted (p < 0.01). Immunohistochemical analyses showed the collagen III expression in the islet capsule of the RCP+ADSCs-4w group was significantly enhanced in comparison to the RCP-4w and RCP+ADSCs-d10 groups (p < 0.01, p < 0.01). In addition, the number of von Willebrand factor-positive vessels within islets in the RCP+ADSCs-4w group was significantly higher than the RCP-4w group. These results suggest that using ADSCs in combination with an RCP device could enhance the restoration of the extracellular matrices, induce more efficient prevascularization within islets, and improve the graft function.

Blood flow ratio in the gastric conduit measured by laser Doppler flowmetry: A predictor of anastomotic leakage after esophagectomy

Background

Anastomotic leakage after esophagectomy is a common complication. Laser Doppler flowmetry (LDF) can quantitatively evaluate the blood flow in the gastric conduit.

Methods

A total of 326 patients who underwent thoracoscopic/robot-assisted esophagectomy followed by gastric conduit reconstruction and end-to-side anastomosis were enrolled. We divided the gastric conduit into zones I (dominated by the right gastroepiploic vessels), II (dominated by the left gastroepiploic vessels), and III (perfused with short gastric vessels). Before pulling up the gastric conduit to the neck, LDF values were measured at the pylorus, the border between zones I and II (zone I/II), the border between zones II and III (zone II/III), and the gastric conduit tip (tip). The blood flow ratio was calculated as the LDF value divided by the LDF value at the pylorus.

Results

Anastomotic leakage developed in 32 of 326 patients. Leakage was significantly associated with the blood flow ratio at the tip (p < 0.001), but not at zone I/II, zone II/III, and the anastomotic site. The receiver-operating characteristic curve analysis identified an anastomotic leakage cutoff ratio of 0.41 (at the tip). A multivariate Cox analysis showed that a blood flow ratio <0.41 at the tip was an independent risk factor for anastomotic leakage (p < 0.001).

Conclusion

Anastomotic leakage after esophagectomy was significantly associated with the blood flow ratio at the tip of the gastric conduit. Preservation of the blood supply to the tip via the gastric wall might contribute to a decreased incidence of anastomotic leakage.

Current status and therapeutic strategy of acute acalculous cholecystitis: Japanese nationwide survey in the era of the Tokyo guidelines

PURPOSE

This study aimed to clarify the incidence, therapeutic modality, and prognosis of acute acalculous cholecystitis and to reveal its optimal treatment strategy.

METHODS

As a project study of the Japanese Society for Abdominal Emergency Medicine, we performed a questionnaire survey of demographic data and perioperative outcomes of acute acalculous cholecystitis treated between January 2018 and December 2020 from 42 institutions.

RESULTS

In this study, 432 patients of acute acalculous cholecystitis, which accounts for 7.04% of acute cholecystitis, were collected. According to the Tokyo guidelines severity grade, 167 (38.6%), 202 (46.8%), and 63 (14.6%) cases were classified as Grade I, II, and III, respectively. A total of 11 (2.5%) patients died and myocardial infarction/congestive heart failure was the only independent risk factor for in-hospital death. Cholecystectomy, especially the laparoscopic approach, had more preferable outcomes compared to their counterparts. The Tokyo guidelines flow charts were useful for Grade I and II severity, but in the cases with Grade III, upfront cholecystectomy could be suitable in some patients.

CONCLUSIONS

The proportions of severity grade and mortality of acute acalculous cholecystitis were found to be similar to those of acute cholecystitis, and laparoscopic cholecystectomy is recommended as an effective treatment option. (UMIN000047631).

A multi-institutional randomized phase III study comparing minimally invasive distal pancreatectomy versus open distal pancreatectomy for pancreatic cancer; Japan Clinical Oncology Group study JCOG2202 (LAPAN study)

BACKGROUND

Minimally invasive distal pancreatectomy (MIDP), including laparoscopic and robotic distal pancreatectomy, has gained widespread acceptance over the last decade owing to its favorable short-term outcomes. However, evidence regarding its oncologic safety is insufficient. In March 2023, a randomized phase III study was launched in Japan to confirm the non-inferiority of overall survival in patients with resectable pancreatic cancer undergoing MIDP compared with that of patients undergoing open distal pancreatectomy (ODP).

METHODS

This is a multi-institutional, randomized, phase III study. A total of 370 patients will be enrolled from 40 institutions within 4 years. The primary endpoint of this study is overall survival, and the secondary endpoints include relapse-free survival, proportion of patients undergoing radical resection, proportion of patients undergoing complete laparoscopic surgery, incidence of adverse surgical events, and length of postoperative hospital stay. Only a credentialed surgeon is eligible to perform both ODP and MIDP. All ODP and MIDP procedures will undergo centralized review using intraoperative photographs. The non-inferiority of MIDP to ODP in terms of overall survival will be statistically analyzed. Only if non-inferiority is confirmed will the analysis assess the superiority of MIDP over ODP.

DISCUSSION

If our study demonstrates the non-inferiority of MIDP in terms of overall survival, it would validate its short-term advantages and establish its long-term clinical efficacy.

TRIAL REGISTRATION

This trial is registered with the Japan Registry of Clinical Trials as jRCT 1,031,220,705 [ https://jrct.niph.go.jp/en-latest-detail/jRCT1031220705 ].

Machine Learning of Histopathological Images Predicts Recurrences of Resected Pancreatic Ductal Adenocarcinoma With Adjuvant Treatment

OBJECTIVES

Pancreatic ductal adenocarcinoma is an intractable disease with frequent recurrence after resection and adjuvant therapy. The present study aimed to clarify whether artificial intelligence-assisted analysis of histopathological images can predict recurrence in patients with pancreatic ductal adenocarcinoma who underwent resection and adjuvant chemotherapy with tegafur/5-chloro-2,4-dihydroxypyridine/potassium oxonate.

MATERIALS AND METHODS

Eighty-nine patients were enrolled in the study. Machine-learning algorithms were applied to 10-billion-scale pixel data of whole-slide histopathological images to generate key features using multiple deep autoencoders. Areas under the curve were calculated from receiver operating characteristic curves using a support vector machine with key features alone and by combining with clinical data (age and carbohydrate antigen 19-9 and carcinoembryonic antigen levels) for predicting recurrence. Supervised learning with pathological annotations was conducted to determine the significant features for predicting recurrence.

RESULTS

Areas under the curves obtained were 0.73 (95% confidence interval, 0.59-0.87) by the histopathological data analysis and 0.84 (95% confidence interval, 0.73-0.94) by the combinatorial analysis of histopathological data and clinical data. Supervised learning model demonstrated that poor tumor differentiation was significantly associated with recurrence.

CONCLUSIONS

Results indicate that machine learning with the integration of artificial intelligence-driven evaluation of histopathological images and conventional clinical data provides relevant prognostic information for patients with pancreatic ductal adenocarcinoma.

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 β (PRKACB), phosphorylated cAMP response element-binding protein, and aberrations of p16, p53, SMAD4, STK11, and β-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.

Immunohistochemical and in situ hybridization analyses of glucose transporter 2 in pancreatic neuroendocrine tumors: Possible glucose transporter 2 association with neoplastic insulin production

BACKGROUND

Pancreatic neuroendocrine tumors (PanNETs) are rare neoplasms. Additionally, glucose transporter 2 (GLUT2) is associated with insulin production and is essential for glucose transport to normal pancreatic β-cells. Neoplastic cell GLUT2 expression may also influence insulin production by using this transporter. GLUT2 expression and its clinical significance remain unclear in PanNETs. This study aimed to provide GLUT2 expression profiles and evidence of correlation with insulin in PanNETs.

METHODS

Clinical data were retrieved from 113 surgically resected paraffin-embedded PanNET tissue samples fixed with 10% formalin. PanNETs are categorized as insulinoma, non-functional (NF)-PanNET, or PanNET-not otherwise specified (NOS). A GLUT2 score was used to evaluate cytoplasmic GLUT2 immunoreactivity. The immunoreactive score (IRS) was used to determine membranous GLUT2, cytoplasmic insulin, and proinsulin immunoreactivities. A commercially available in situ hybridization (ISH) kit detected human SLC2A2 (GLUT2) mRNA on tissues in all seven positive- and 20 negative-GLUT2 IRS cases.

RESULTS

GLUT2 and IRSs significantly differed among insulinoma, NF-PanNET, and PanNET-NOS. Insulinomas exhibited significantly higher GLUT2 scores and IRSs than did NF-PanNETs. GLUT2 IRS positive cases demonstrated significantly higher insulin and proinsulin IRSs than did negative cases. Additionally, GLUT2 ISH-positive cases demonstrated positive GLUT2 scores and IRSs, with significantly higher GLUT2 IRSs than did negative cases. PanNET histological grade categories did not significantly affect GLUT2 scores and IRSs.

CONCLUSION

The first evidence of a correlation between GLUT2 expressions and insulin in PanNETs is shown in this study.

A Gelatin Hydrogel Nonwoven Fabric Enhances Subcutaneous Islet Engraftment in Rats

Although subcutaneous islet transplantation has many advantages, the subcutaneous space is poor in vessels and transplant efficiency is still low in animal models, except in mice. Subcutaneous islet transplantation using a two-step approach has been proposed, in which a favorable cavity is first prepared using various materials, followed by islet transplantation into the preformed cavity. We previously reported the efficacy of pretreatment using gelatin hydrogel nonwoven fabric (GHNF), and the length of the pretreatment period influenced the results in a mouse model. We investigated whether the preimplantation of GHNF could improve the subcutaneous islet transplantation outcomes in a rat model. GHNF sheets sandwiching a silicone spacer (GHNF group) and silicone spacers without GHNF sheets (control group) were implanted into the subcutaneous space of recipients three weeks before islet transplantation, and diabetes was induced seven days before islet transplantation. Syngeneic islets were transplanted into the space where the silicone spacer was removed. Blood glucose levels, glucose tolerance, immunohistochemistry, and neovascularization were evaluated. The GHNF group showed significantly better blood glucose changes than the control group (p < 0.01). The cure rate was significantly higher in the GHNF group (p < 0.05). The number of vWF-positive vessels was significantly higher in the GHNF group (p < 0.01), and lectin angiography showed the same tendency (p < 0.05). The expression of laminin and collagen III around the transplanted islets was also higher in the GHNF group (p < 0.01). GHNF pretreatment was effective in a rat model, and the main mechanisms might be neovascularization and compensation of the extracellular matrices.

Small Intestinal Adenocarcinoma Arising at the Anastomotic Site after Kasai Operation for Biliary Atresia: A Case Report and Literature Review

Biliary atresia is an obliterative cholangiopathy of unknown etiology. Hepatic portoenterostomy, in which obliterated extrahepatic bile ducts are resected and bile flow is restored, known as Kasai operation, is performed within 3 months after birth. While this operation enhances long-term survival of patients, the occurrence of primary malignant hepatic tumors has been increasing. We report a case of small intestinal adenocarcinoma arising at the anastomotic site after Kasai operation. A 49-year-old man, who underwent Kasai operation for biliary atresia when he was 2 months old, experienced rapidly progressive jaundice and liver dysfunction. Deceased-donor liver transplantation was performed for liver failure. Macroscopically, there was a white-yellow tumor located at the anastomotic site of hepatic portoenterostomy of the resected liver. Pathological examination revealed a well-differentiated adenocarcinoma with some Paneth cells in the neoplastic lesion. Immunohistochemically, the tumor cells were negative for cytokeratin 7 (CK7) but positive for cytokeratin 20 (CK20) and a homeobox domain-containing transcription factor (CDX2). Mucin expression in tumor cells was negative for mucin 1 (MUC1) and mucin 6 (MUC6) and positive for mucin 2 (MUC2) and mucin 5AC (MUC5AC). The pathological diagnosis was small intestinal adenocarcinoma originating from the jejunum. The patient was discharged 48 days after the operation. The patient had not experienced recurrence at 10 months after the operation. This is the first report of small intestinal adenocarcinoma arising at the anastomotic site after Kasai operation for biliary atresia. Special care should be taken for the patients after Kasai operation with acute progressive jaundice and liver dysfunction because there is a possibility of malignancy in their native liver.

Chronic Glucocorticoid Use is a Potential Risk Factor for Delayed Pancreatic Fistula after Laparoscopic Distal Pancreatectomy: A Retrospective Analysis

Pancreatic fistula is a potentially morbid complication after distal pancreatectomy. Chronic glucocorticoid use is one of the risk factors for pancreatic fistula in pancreaticoduodenectomy, though it has not been reported in distal pancreatectomy. We explored whether chronic glucocorticoid use can be a risk factor for pancreatic fistula in distal pancreatectomy. We reviewed 408 consecutive patients who underwent elective distal pancreatectomy from 2011 to 2021. We evaluated two kinds of pancreatic fistula (postoperative pancreatic fistula and delayed pancreatic fistula). We defined delayed pancreatic fistula as a patient who was re-admitted for pancreatic fistula after the first discharge from the hospital. Preoperative characteristics and postoperative outcomes were analyzed. Two hundred sixty-seven patients underwent open distal pancreatectomy, while 141 patients had laparoscopic distal pancreatectomy. A comparison of patient with and without chronic glucocorticoid use showed that only patients with chronic glucocorticoid use developed delayed pancreatic fistula (0% vs. 16.7%; p < 0.001). In addition, delayed pancreatic fistula occurred in only laparoscopic distal pancreatectomy patients with chronic glucocorticoid use (0% vs. 25.0%; p < 0.001). Although sample size is small, it is reasonable to presume that chronic glucocorticoid use is a potential risk factor for delayed pancreatic fistula in laparoscopic distal pancreatectomy.

A case of percutaneous transhepatic portal vein stenting without using iodinated contrast media for post pancreatectomy portal vein obstruction

Postoperative portal vein obstruction could occur as a complication of portal vein reconstruction during hepatic lobectomy or pancreaticoduodenectomy. We report a case of patient with postoperative portal vein obstruction treated with percutaneous transhepatic portal vein stenting without using iodinated contrast media owing to a history of severe allergic reactions. Under ultrasound guidance, carbon dioxide angiography, and appropriate device selection, successful stenting was achieved without serious adverse events. After the operation, portal vein blood flow and clinical symptoms improved, enabling adjuvant chemotherapy. To the best of our knowledge, this is the first case report wherein percutaneous transhepatic portal vein stenting was successfully performed in a patient with an iodine allergy.

Collagen XVII regulates tumor growth in pancreatic cancer through interaction with the tumor microenvironment

Expression of the gene for collagen XVII (COL17A1) in tumor tissue is positively or negatively associated with patient survival depending on cancer type. High COL17A1 expression is thus a favorable prognostic marker for breast cancer but unfavorable for pancreatic cancer. This study explored the effects of COL17A1 expression on pancreatic tumor growth and their underlying mechanisms. Analysis of published single-cell RNA-sequencing data for human pancreatic cancer tissue revealed that COL17A1 was expressed predominantly in cancer cells rather than surrounding stromal cells. Forced expression of COL17A1 did not substantially affect the proliferation rate of the mouse pancreatic cancer cell lines KPC and AK4.4 in vitro. However, in mouse homograft tumor models in which KPC or AK4.4 cells were injected into syngeneic C57BL/6 or FVB mice, respectively, COL17A1 expression promoted or suppressed tumor growth, respectively, suggesting that the effect of COL17A1 on tumor growth was influenced by the tumor microenvironment. RNA-sequencing analysis of tumor tissue revealed effects of COL17A1 on gene expression profiles (including the expression of genes related to cell proliferation, the immune response, Wnt signaling, and Hippo signaling) that differed between C57BL/6-KPC and FVB-AK4.4 tumors. Our data thus suggest that COL17A1 promotes or suppresses cancer progression in a manner dependent on the interaction of tumor cells with the tumor microenvironment.

Prognostic impact of postoperative infection after resection of biliary malignancy: A multicenter retrospective cohort study

BACKGROUND

The aim of this study was to investigate the prognostic impact of postoperative infections in patients who underwent resection for biliary malignancy, including intrahepatic cholangiocarcinoma, perihilar cholangiocarcinoma, distal cholangiocarcinoma, gallbladder carcinoma, and carcinoma of the ampulla of Vater.

METHODS

This study was conducted in an 11-center retrospective cohort study. Patients with biliary tract cancer who underwent curative resection between April 2013 and March 2015 at 11 institutions in Japan were enrolled. We analyzed the prevalence of postoperative infection, infection-related factors, and prognostic factors.

RESULTS

Of the total 290 cases, 33 were intrahepatic cholangiocarcinoma, 60 were perihilar cholangiocarcinoma, 120 were distal cholangiocarcinoma, 55 were gallbladder carcinoma, and 22 were carcinoma of the ampulla of Vater. Postoperative infectious complications, including remote infection, were observed in 146 patients (50.3%), and Clavien-Dindo ≥III in 115 patients (39.7%). Postoperative infections occurred more commonly in the patients who received pancreaticoduodenectomy and bile duct resection. Patients with infectious complications had a significantly poorer prognosis than those without (median overall survival 38 months vs 62 months, P = .046). In a diagnosis-specific analysis, although there was no correlation between infectious complications and overall survival in intrahepatic cholangiocarcinoma, perihilar cholangiocarcinoma, distal cholangiocarcinoma, and carcinoma of the ampulla of Vater, infectious complications were a significantly poor prognostic factor in gallbladder carcinoma (P = .031).

CONCLUSION

Postoperative infection after surgery for biliary tract cancer commonly occurred, especially in patients who underwent pancreaticoduodenectomy and bile duct resection. Postoperative infection is relatively associated with the prognosis of patients with biliary malignancy, especially gallbladder carcinoma.

CA19-9 With Two-stage Resection Is Useful for Conversion Surgery in PDAC With Synchronous Oligometastases

BACKGROUND/AIM

Pancreatic adenocarcinoma (PDAC) with synchronous oligometastases may indicate a surgical benefit after chemotherapy. We investigated whether primary and metastatic resection of PDAC with oligometastases can improve the survival and then explored prognostic factors to identify indications for conversion surgery.

PATIENTS AND METHODS

We reviewed 425 patients with PDAC who underwent pancreatic resection from 2005 to 2019. Clinical characteristics and outcomes were analyzed. Two-stage resection was defined as preceding metastasectomy and subsequent primary resection after chemotherapy.

RESULTS

Fifteen patients (3.5%) had synchronous oligometastases. We evaluated the overall survival of the patients with oligometastases and those without metastases. The survival curves almost completely overlapped (median survival time: 35.9 vs. 32.1 months). The univariate Cox regression analysis revealed a normal level of preoperative CA19-9 (p=0.075), two-stage resection (p=0.072), and R0 resection (p=0.064) were likely promising prognostic factors. The combination of a normal level of preoperative CA19-9 with two-stage resection was a significant prognostic factor (p=0.038). In addition, patients with a normal preoperative CA19-9 level and two-stage resection had better survival (46.1 vs. 28.1 months, p=0.026).

CONCLUSION

The combination of normal preoperative CA19-9 with two-stage resection can be a useful way to identify patients with PDAC and oligometastases for surgical indication.

Living-Donor Liver Transplantation for Erythropoietic Protoporphyria: A Case Report and Literature Review

Erythropoietic protoporphyria (EPP) is a very rare disease with an estimated prevalence of 1 in 200,000 individuals. Decreased ferrochelatase activity causes the accumulation of protoporphyrin in the body, and light exposure results in the generation of active oxygen, causing photosensitivity. Liver damage has the greatest influence on the prognosis, and liver transplantation is the only treatment option for patients with decompensated liver cirrhosis. We report a case of living-donor liver transplantation for decompensated liver cirrhosis associated with EPP. The patient was a 52-year-old male who led a normal life except for mild photosensitivity. When the patient was 37-year-old, hepatic dysfunction was noticed. At 48-year-old, high erythrocyte protoporphyrin levels, skin biopsy, and genetic tests resulted in a diagnosis of EPP. The patient underwent living- donor liver transplantation because of decompensated liver cirrhosis. In the operating room and intensive care unit, a special light-shielding film was applied to all light sources to block light with harmful wavelengths during treatment. Due to the need for special measures, a lecture on patients with EPP was given before surgery to deepen understanding among all medical professionals involved in the treatment. As a result, no adverse events occurred during the perioperative period, and the patient was discharged on the 46th post-operative day. Currently, the transplanted liver is functioning extremely well, and the patient is alive 3 years post-transplant. Herein, we describe a case of living donor liver transplantation for EPP with a brief literature review.

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.

Tumor-to-Tumor Metastasis of Medullary Thyroid Carcinoma to Paraganglioma in a Multiple Endocrine Neoplasia Type 2B Patient: A Case Report and Literature Review

Tumor-to-tumor metastasis is a rare phenomenon in which primary tumor cells metastasize to other tumors. Herein, we report an extremely rare case of tumor-to-tumor metastasis of medullary thyroid carcinoma to a paraganglioma in a patient with multiple endocrine neoplasia type 2B. Based on genetic examination, a 36-year-old woman was diagnosed with multiple endocrine neoplasia type 2B when she was 24 years old. She had a history of total thyroidectomy for medullary thyroid carcinoma and bilateral adrenalectomy for pheochromocytomas, which were performed when she was 15 years and 29 years old, respectively. Follow-up computed tomography demonstrated a retroperitoneal tumor of 30 mm in diameter beside the left kidney and a liver tumor of 16 mm in diameter located in segment 6. The retroperitoneal and liver tumors were surgically resected and examined by a pathologist. Histological examination revealed the classic Zellballen pattern in the retroperitoneal tumor, rendering the diagnosis of a paraganglioma recurrence. Inside the tumor, a white nodule positive for carcinoembryonic antigen, weakly positive for calcitonin, and negative for tyrosine hydroxylase, was identified and diagnosed as a metastatic medullary thyroid carcinoma with high malignant potential. The liver lesion was diagnosed as a metastasis of the medullary thyroid carcinoma. This is the first report of tumor-to-tumor metastasis of medullary thyroid carcinoma to paraganglioma in a patient with multiple endocrine neoplasia type 2B twenty years after total thyroidectomy.

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.

Reduced expression of phosphorylated ataxia-telangiectasia mutated gene is related to poor prognosis and gemcitabine chemoresistance in pancreatic cancer

BACKGROUND

Loss of expression of the gene ataxia-telangiectasia mutated (ATM), occurring in patients with multiple primary malignancies, including pancreatic cancer, is associated with poor prognosis. In this study, we investigated the detailed molecular mechanism through which ATM expression affects the prognosis of patients with pancreatic cancer.

METHODS

The levels of expression of ATM and phosphorylated ATM in patients with pancreatic cancer who had undergone surgical resection were analyzed using immunohistochemistry staining. RNA sequencing was performed on ATM-knockdown pancreatic-cancer cells to elucidate the mechanism underlying the invlovement of ATM in pancreatic cancer.

RESULTS

Immunohistochemical analysis showed that 15.3% and 27.8% of clinical samples had low levels of ATM and phosphorylated ATM, respectively. Low expression of phosphorylated ATM substantially reduced overall and disease-free survival in patients with pancreatic cancer. In the pancreatic cancer cell lines with ATM low expression, resistance to gemcitabine was demonstrated. The RNA sequence demonstrated that ATM knockdown induced the expression of MET and NTN1. In ATM knockdown cells, it was also revealed that the protein expression levels of HIF-1α and antiapoptotic BCL-2/BAD were upregulated.

CONCLUSIONS

These findings demonstrate that loss of ATM expression increases tumor development, suppresses apoptosis, and reduces gemcitabine sensitivity. Additionally, loss of phosphorylated ATM is associated with a poor prognosis in patients with pancreatic cancer. Thus, phosphorylated ATM could be a possible target for pancreatic cancer treatment as well as a molecular marker to track patient prognosis.

Features of T1 pancreatic cancer and validation of the eighth edition AJCC staging system definition using a Korean-Japanese joint cohort and the SEER database

BACKGROUND/PURPOSE

Little is known about the features of T1 pancreatic ductal adenocarcinoma (PDAC) and its definition in the eighth edition of the American Joint Committee on Cancer (AJCC) staging system needs validation. The aims were to analyze the clinicopathologic features of T1 PDAC and investigate the validity of its definition.

METHOD

Data from 1506 patients with confirmed T1 PDAC between 2000 and 2019 were collected and analyzed. The results were validated using 3092 T1 PDAC patients from the Surveillance, Epidemiology, and End Results (SEER) database.

RESULTS

The median survival duration of patients was 50 months, and the 5-year survival rate was 45.1%. R0 resection was unachievable in 10.0% of patients, the nodal metastasis rate was 40.0%, and recurrence occurred in 55.2%. The current T1 subcategorization was not feasible for PDAC, tumors with extrapancreatic extension (72.8%) had worse outcomes than those without extrapancreatic extension (median survival 107 vs. 39 months, p < .001). Extrapancreatic extension was an independent prognostic factor whereas the current T1 subcategorization was not. The results of this study were reproducible with data from the SEER database.

CONCLUSION

Despite its small size, T1 PDAC displayed aggressive behavior warranting active local and systemic treatment. The subcategorization by the eighth edition of the AJCC staging system was not adequate for PDAC, and better subcategorization methods need to be explored. In addition, the role of extrapancreatic extension in the staging system should be reconsidered.

Clinical impact of multimodal treatment including chemoradiotherapy, conversion surgery and postoperative chemotherapy for borderline resectable and unresectable locally advanced pancreatic cancer without disease progression after gemcitabine plus nab-paclitaxel

BACKGROUND

The purpose of this study was to investigate treatment outcomes of chemoradiotherapy (CRT) using S-1 with or without conversion surgery after gemcitabine plus nab-paclitaxel (GnP) for borderline resectable (BR) and unresectable locally advanced (UR-LA) pancreatic cancer.

METHODS

From 2016 to 2020, patients without disease progression after GnP for BR or UR-LA pancreatic cancer underwent CRT with S-1. If distant metastasis was not detected after CRT, conversion surgery and oral administration of S-1 as postoperative adjuvant chemotherapy for at least 6 months was performed.

RESULTS

Forty patients were included in the present study. The median number of cycles of GnP was 6. Surgery was performed after CRT in 25 patients. The median progression-free survival (PFS) and overall survival (OS) periods from the start of radiotherapy were 24.6 and 27.4 months, respectively. The OS periods from the start of radiotherapy in patients who underwent conversion surgery and those who did not undergo conversion surgery were 41.3 and 16.8 months, respectively. The PFS periods from the start of radiotherapy in patients who underwent surgery and those who did not undergo surgery were 28.3 and 8.6 months, respectively. Patients who were able to receive S-1 after conversion surgery for more than 6 months had better OS than those who were not (p = 0.039), although there was no significant difference of PFS (p = 0.365).

CONCLUSIONS

In BR/UR-LA pancreatic cancer without disease progression after GnP, multimodal treatment including CRT, conversion surgery and the scheduled postoperative chemotherapy may be effective.

Evidence-based clinical practice guidelines for cholelithiasis 2021

The Japanese Society of Gastroenterology first published evidence-based clinical practice guidelines for cholelithiasis in 2010, followed by a revision in 2016. Currently, the revised third edition was published to reflect recent evidence on the diagnosis, treatment, and prognosis of cholelithiasis conforming to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. Following this revision, the present English version of the guidelines was updated and published herein. The clinical questions (CQ) in the previous version were reviewed and rearranged into three newly divided categories: background questions (BQ) dealing with basic background knowledge, CQ, and future research questions (FRQ), which refer to issues that require further accumulation of evidence. Finally, 52 questions (29 BQs, 19 CQs, and 4 FRQs) were adopted to cover the epidemiology, pathogenesis, diagnosis, treatment, complications, and prognosis. Based on a literature search using MEDLINE, Cochrane Library, and Igaku Chuo Zasshi databases for the period between 1983 and August 2019, along with a manual search of new information reported over the past 5 years, the level of evidence was evaluated for each CQ. The strengths of recommendations were determined using the Delphi method by the committee members considering the body of evidence, including benefits and harms, patient preference, and cost-benefit balance. A comprehensive flowchart was prepared for the diagnosis and treatment of gallbladder stones, common bile duct stones, and intrahepatic stones, respectively. The current revised guidelines are expected to be of great assistance to gastroenterologists and general physicians in making decisions on contemporary clinical management for cholelithiasis patients.

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.

A gelatin hydrogel nonwoven fabric improves outcomes of subcutaneous islet transplantation

Subcutaneous islet transplantation is a promising treatment for severe diabetes; however, poor engraftment hinders its prevalence. We previously reported that a recombinant peptide (RCP) enhances subcutaneous islet engraftment. However, it is impractical for clinical use because RCP must be removed when transplanting islets. We herein investigated whether a novel bioabsorbable gelatin hydrogel nonwoven fabric (GHNF) could improve subcutaneous islet engraftment. A silicon spacer with or without GHNF was implanted into the subcutaneous space of diabetic mice. Syngeneic islets were transplanted into the pretreated space or intraportally (Ipo group). Blood glucose, intraperitoneal glucose tolerance, immunohistochemistry, CT angiography and gene expression were evaluated. The cure rate and glucose tolerance of the GHNF group were significantly better than in the control and Ipo groups (p < 0.01, p < 0.05, respectively). In the GHNF group, a limited increase of vWF-positive vessels was detected in the islet capsule, whereas laminin (p < 0.05), collagen III and IV were considerably enhanced. TaqMan arrays revealed a significant upregulation of 19 target genes (including insulin-like growth factor-2) in the pretreated space. GHNF markedly improved the subcutaneous islet transplantation outcomes, likely due to ECM compensation and protection of islet function by various growth factors, rather than enhanced neovascularization.

Feasibility of Surveillance for Mucinous Cystic Neoplasm of the Pancreas: A Multi-Institutional Retrospective Study of 328 Patients by the Japanese Pancreatic Society

OBJECTIVE

We aimed to elucidate the feasibility of surveillance of patients with mucinous cystic neoplasm (MCN).

METHODS

We performed a retrospective, multi-institutional study of 328 patients who underwent surgery for MCN at 18 Japanese institutions. Patients with MCN were divided into an immediate surgery group and a surveillance group, which underwent surgery after surveillance.

RESULTS

The median surveillance period until surgery in the surveillance group was 27 months (range, 7-165 months). Compared with the immediate surgery group, the surveillance group showed smaller tumor diameter (46 vs 50 mm, P = 0.01), more frequent laparoscopic approach (58% vs 37%, P < 0.01), and less frequent malignancy (7% vs 15%, P = 0.03). The new appearance of mural nodules and elevation of serum tumor markers were associated with malignancy in the surveillance group. Two patients in the surveillance group experienced postoperative recurrence, although there was no significant difference in recurrence or disease-free survival between the two groups. In the surveillance group, the 1-, 5-, and 10-year cumulative incidence rates of malignant MCN were 0.8%, 5.6%, and 36.5%, respectively.

CONCLUSION

As the risk of progression to malignant MCNs increases over the long term, MCNs should be resected rather than subjected to unnecessary surveillance.

Clinical Significance of the Mac-2 Binding Protein Glycosylated Isomer as a Surrogate Marker of Graft Fibrosis After Pediatric Liver Transplantation

BACKGROUND

After pediatric liver transplantation, liver fibrosis may occur during long-term follow-up. Noninvasive markers for assessing this liver fibrosis are desired. Mac-2 binding protein glycosylated isomer (M2BPGi) has recently been reported as a useful biomarker for liver fibrosis. However, its usefulness in the pediatric population is yet to be established. This study investigated the clinical significance of M2BPGi levels as a surrogate marker of graft fibrosis after pediatric liver transplantation.

METHODS

We retrospectively identified 96 patients who underwent pediatric liver transplantation at our institution between 1991 and 2015. The association between M2BPGi levels and other fibrosis markers was analyzed in 60 patients in whom fibrosis markers were measured. The association between fibrosis marker levels and graft fibrosis was assessed in 42 patients who underwent biopsies between 2016 and 2022.

RESULTS

The M2BPGi levels were statistically correlated with the hyaluronic acid and type-IV collagen levels. None of the fibrosis markers were significantly associated with liver graft fibrosis, although the levels of these markers were slightly higher in patients with severe liver fibrosis than in those with mild fibrosis.

CONCLUSIONS

The M2BPGi levels had a limited ability to assess liver graft fibrosis after pediatric liver transplantation, similar to other fibrosis markers. Further studies with larger cohorts are required to validate these findings externally.

Ral GTPase promotes metastasis of pancreatic ductal adenocarcinoma via elevation of TGF-β1 production

Pancreatic ductal adenocarcinoma (PDAC), caused by activating mutations in K-Ras, is an aggressive malignancy due to its early invasion and metastasis. Ral GTPases are activated downstream of Ras and play a crucial role in the development and progression of PDAC. However, the underlying mechanisms remain unclear. In this study, we investigated the mechanism of Ral-induced invasion and metastasis of PDAC cells using RalGAPβ-deficient PDAC cells with highly activated Ral GTPases. Array analysis and enzyme-linked immunosorbent assays revealed increased expression and secretion of TGF-β1 in RalGAPβ-deficient PDAC cells compared to control cells. Blockade of TGF-β1 signaling suppressed RalGAPβ deficiency-enhanced migration and invasion in vitro and metastasis in vivo to levels similar to controls. Phosphorylation of c-Jun N-terminal kinase (JNK), a repressor of TGF-β1 expression, was decreased by RalGAPβ deficiency. These results indicate that Ral contributes to invasion and metastasis of PDAC cells by elevating autocrine TGF-β1 signaling at least in part by decreasing JNK activity.

Functional Assessment of Cardiac Arrest Hepatocytes and Effect of Mechanical Perfusion on Function in a Rat Model

BACKGROUND

Hepatocyte transplantation has been reported to be useful for metabolic diseases and acute liver failure. However, the shortage of donors limits its widespread use. The use of livers from donors after circulatory death, which are currently unavailable for liver transplantation, may alleviate donor shortage. In this study, we investigated the effects of mechanical perfusion on cardiac arrest hepatocytes in a rat model using cardiac arrest donor livers, and we evaluated the function of cardiac arrest hepatocytes.

METHODS

F344 rat hepatocytes isolated from livers removed during cardiac pulsation were compared with those isolated from livers removed after 30 minutes of warm ischemia after cardiac arrest. We then compared hepatocytes isolated from livers removed after 30 minutes of warm ischemia with those isolated after 30 minutes of mechanical perfusion before isolation. The yield per liver weight, ammonia removal capacity, and adenosine diphosphate/adenosine triphosphate ratio were evaluated.

RESULTS

Thirty minutes of warm inhibition reduced hepatocyte yield but did not alter ammonia removal capacity and energy status. Mechanical perfusion increased hepatocyte yield and improved the adenosine diphosphate/adenosine triphosphate ratio after 30 minutes of warm inhibition.

CONCLUSION

Thirty minutes of warm ischemic time may decrease isolated hepatocyte yield without degrading their function. If increased yields are obtained, livers from donors dying of cardiac arrest could be used for hepatocyte transplantation. The results also suggest that mechanical perfusion may positively affect the energy status of hepatocytes.

Infliximab Inhibits Colitis Associated Cancer in Model Mice by Downregulating Genes Associated with Mast Cells and Decreasing Their Accumulation

Inflammatory bowel diseases (IBDs), such as Crohn’s disease or ulcerative colitis, can be treated with anti TNF-alpha (TNF-α) antibodies (Abs), but they also put patients with IBDs at risk of cancer. We aimed to determine whether the anti TNF-α Ab induces colon cancer development in vitro and in vivo, and to identify the genes involved in colitis-associated cancer. We found that TNF-α (50 ng/mL) inhibited the proliferation, migration, and invasion of HCT8 and COLO205 colon cancer cell lines and that anti TNF-α Ab neutralized TNF-α inhibition in vitro. The effects of anti TNF-α Ab, infliximab (10 mg/kg) were investigated in mouse models of colitis-associated cancer induced by intraperitoneally injected azoxymethane (AOM: 10 mg/kg)/orally administered dextran sodium sulfate (DSS: 2.5%) (AOM/DSS) in vivo. Infliximab significantly attenuated the development of colon cancer in these mice. Microarray analyses and RT-qPCR revealed that mast cell protease 1, mast cell protease 2, and chymase 1 were up-regulated in cancer tissue of AOM/DSS mice; however, those mast cell related genes were downregulated in cancer tissue of AOM/DSS mice with infliximab. These results suggested that mast cells play a pivotal role in the development of cancer associated with colitis in AOM/DSS mice.

Preservation of remnant esophagus during total pharyngolaryngectomy in a patient with previous subtotal esophagectomy: a case report

Background

With the improved survival rate of patients with esophageal cancer, secondary cancers, including pharyngolaryngeal cancer, have become a problem. Phanryngolaryngeal cancer surgery often requires esophagogastric anastomosis resection in patients with a previous history of subtotal esophagectomy. Owing to adhesions, especially surrounding the esophagogastric anastomosis, caused by the initial surgery, the second surgery might cause postoperative complications.

Case presentation

A 65-year-old man was diagnosed with early stage esophageal squamous cell carcinoma and underwent endoscopic mucosal dissection. However, the histopathological depth of the tumor was pT1b, and additional treatment was required. After administration of the neoadjuvant chemotherapy, he underwent thoracoscopic esophagectomy and retrosternum reconstruction via a gastric tube (pT1N3M0 stage III). Eight months after the first surgery, tumor recurrences were observed at the anastomosis and left cervical lymph node. Definitive chemoradiotherapy was performed for the recurrences, and complete response was achieved. Seven months after chemoradiotherapy, he was diagnosed with hypopharyngeal squamous cell carcinoma in the right piriform fossa (cT2N2bM0 stage IVA), and salvage surgery was chosen as treatment. The surgical findings revealed strong adhesion around the remnant esophagus, which was difficult to dissect from surrounding tissue and was associated with a risk of breaking of the anastomosis. However, indocyanine green fluorescence imaging findings indicated sufficient blood flow to preserve the remnant esophagus, including the anastomosis, even after the interruption of blood flow from the proximal side of the esophagus by total pharyngolaryngectomy. Finally, approximately 4 cm of the remnant esophagus was preserved, and the free jejunum reconstruction with cervical vascular anastomosis was performed. Moreover, the patient was discharged without complications on postoperative day 38. After 10 months of the second surgery, a metastatic lymph node was observed in the right neck. Immune checkpoint inhibitors and chemotherapy were administered, and the patient is alive and under treatment 1.5 years after the second surgery.

Conclusions

Blood supply to the remnant cervical esophagus was thought to be from the gastric conduit over the anastomosis and surrounding capillaries. Thus, the preservation of the remnant esophagus can be considered in total pharyngolaryngectomy even after < 2 years of esophagectomy by blood flow evaluation using indocyanine green fluorescence.

Preservation of remnant esophagus during total pharyngolaryngectomy in a patient with previous subtotal esophagectomy: a case report

BACKGROUND

With the improved survival rate of patients with esophageal cancer, secondary cancers, including pharyngolaryngeal cancer, have become a problem. Phanryngolaryngeal cancer surgery often requires esophagogastric anastomosis resection in patients with a previous history of subtotal esophagectomy. Owing to adhesions, especially surrounding the esophagogastric anastomosis, caused by the initial surgery, the second surgery might cause postoperative complications.

CASE PRESENTATION

A 65-year-old man was diagnosed with early stage esophageal squamous cell carcinoma and underwent endoscopic mucosal dissection. However, the histopathological depth of the tumor was pT1b, and additional treatment was required. After administration of the neoadjuvant chemotherapy, he underwent thoracoscopic esophagectomy and retrosternum reconstruction via a gastric tube (pT1N3M0 stage III). Eight months after the first surgery, tumor recurrences were observed at the anastomosis and left cervical lymph node. Definitive chemoradiotherapy was performed for the recurrences, and complete response was achieved. Seven months after chemoradiotherapy, he was diagnosed with hypopharyngeal squamous cell carcinoma in the right piriform fossa (cT2N2bM0 stage IVA), and salvage surgery was chosen as treatment. The surgical findings revealed strong adhesion around the remnant esophagus, which was difficult to dissect from surrounding tissue and was associated with a risk of breaking of the anastomosis. However, indocyanine green fluorescence imaging findings indicated sufficient blood flow to preserve the remnant esophagus, including the anastomosis, even after the interruption of blood flow from the proximal side of the esophagus by total pharyngolaryngectomy. Finally, approximately 4 cm of the remnant esophagus was preserved, and the free jejunum reconstruction with cervical vascular anastomosis was performed. Moreover, the patient was discharged without complications on postoperative day 38. After 10 months of the second surgery, a metastatic lymph node was observed in the right neck. Immune checkpoint inhibitors and chemotherapy were administered, and the patient is alive and under treatment 1.5 years after the second surgery.

CONCLUSIONS

Blood supply to the remnant cervical esophagus was thought to be from the gastric conduit over the anastomosis and surrounding capillaries. Thus, the preservation of the remnant esophagus can be considered in total pharyngolaryngectomy even after < 2 years of esophagectomy by blood flow evaluation using indocyanine green fluorescence.

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.

Proposal of nomograms to predict clinical outcomes in patients with ampulla of Vater cancer based on the Korea-Japan collaborative study

BACKGROUND

In this study, we aimed to develop and validate a nomogram to predict overall survival (OS) and recurrence-free survival (RFS) in patients who underwent curative resection of ampulla of Vater (AOV) cancer. This is the first study for nomograms in AOV cancer patients using retrospective data based on an international multicenter study.

METHODS

A total of 2007 patients with AOV adenocarcinoma who received operative therapy between 2002 January and 2015 December in Korea and Japan were retrospectively assessed to develop a prediction model. Nomograms for 5-year OS and 3-year RFS were constructed by dividing the patients who received and who did not receive adjuvant therapy after surgery, respectively. Significant risk factors were identified by univariate and multivariate Cox analyses. Performance assessment of the four prediction models was conducted by the Harrell's concordance index (C-index) and calibration curves using bootstrapping.

RESULTS

A total of 2007 and 1873 patients were collected for nomogram construction to predict 5-year OS and 3-year RFS. We developed four types of nomograms, including models for 5-year OS and 3-year RFS in patients who did not receive postoperative adjuvant therapy, and 5-year OS and 3-year RFS in patients who received postoperative adjuvant therapy. The C-indices of these nomograms were 0.795 (95% confidence interval [CI]: 0.766-0.823), 0.712 (95% CI: 0.674-0.750), 0.804 (95% CI: 0.7778-0.829), and 0.703 (95% CI: 0.669-0.737), respectively.

CONCLUSIONS

This predictive model could help clinicians to choose optimal treatment and precisely predict prognosis in AOV cancer patients.

Somatostatin Receptor 2 in 10 Different Types of Human Non-Neoplastic Gastrointestinal Neuroendocrine Cells

Somatostatin is known to inhibit the secretion of various hormones by acting on endocrine cells through the somatostatin receptor 2 (SSTR2). Immunohistochemical evaluation of SSTR2 has become increasingly important in clinical practice to determine treatment strategies for patients with a neuroendocrine tumor (NET). Gastrointestinal (GI) tracts contain various neuroendocrine cells that constitute a diffuse endocrine system and some NETs are derived from those cells. In addition, NETs have been well known to express a variable spectrum of proteins shared by their normal cell counterparts of the specific anatomical sites. Thus, we may derive the kinetics of SSTR2 expression of NETs, including de novo expression, from the SSTR2 expression of the corresponding normal neuroendocrine cells. Therefore, a detailed study on the distribution of SSTR2 in normal human neuroendocrine cells may contribute to understanding the expression of SSTR2 in GI-NETs. However, the detailed cellular localization of SSTR2 in non-neoplastic neuroendocrine cells remains unknown. Therefore, we immunolocalized SSTR2 in neuroendocrine cells of normal human GI tracts, including the stomach, duodenum, ileum, and rectum, obtained from 41 surgically resected tissue specimens. Double immunohistochemistry of SSTR2 and hormones or hormone-associated proteins was performed. In all GI neuroendocrine cells, cell types other than D- and EC-cells demonstrated a high percentage of SSTR2-positive cases or a high double-positive ratio. In particular, EC-cells showed lower SSTR2-positive ratios in all sites. Midgut NETs, which often produce serotonin, are excellent targets for somatostatin analogs and are positive for SSTR2. Thus, we speculated that EC-cell NETs might lead to the de novo expression of SSTR2. In addition, a previous report showed high SSTR2 expression in ECL-cell NETs and gastrinomas, which could be because they are derived from neuroendocrine cells with high SSTR2 expression. This study may contribute to understanding the expression of SSTR2 in GI-NETs.

Simultaneous and sequential combination of genetic and epigenetic biomarkers for the presence of high-grade dysplasia in patients with pancreatic cyst: Discovery in cyst fluid and test in pancreatic juice

BACKGROUND/OBJECTIVES

Screening patients with intraductal papillary mucinous neoplasms (IPMN) has the primary goal of identifying potentially curable noninvasive precursors. We aimed to evaluate the diagnostic impact of genetic and epigenetic biomarkers in the presence of noninvasive precursors.

METHODS

Mutated KRAS/GNAS and methylated SOX17/TBX15/BMP3/TFPI2 DNA were assessed by droplet digital PCR in a discovery cohort of 70 surgically aspirated cyst fluids, and diagnostic performances for differentiating high-grade dysplasia (HGD) from low-grade dysplasia (LGD) was evaluated. We then tested these markers using an independent test cohort consisting of 156 serially collected pancreatic juice samples from 30 patients with IPMN.

RESULTS

Mutated KRAS and GNAS are specific for IPMNs but are not helpful for the prediction of histological grades. Cyst fluids from IPMN with HGD showed higher methylation levels of SOX17 (median, 0.141 vs. 0.021; P = 0.086) and TBX15 (median, 0.030 vs. 0.003; P = 0.028) than those with LGD. The combination of all tested markers yielded a diagnostic performance with sensitivity of 69.6%, and specificity of 90.0%. Among the 30 pancreatic juice samples exhibiting the highest abundance of KRAS/GNAS mutations in each patient in the test cohort, patients with histologically proven HGD due to pancreatic resection had a significantly higher prevalence (100% vs. 31%, P = 0.018) and abundance (P = 0.037) of methylated TBX15 than those without cytohistological diagnosis undergoing surveillance.

CONCLUSIONS

A simultaneous and sequential combination of mutated and methylated DNA markers in pancreatic cyst fluid and juice sample markers can help detect noninvasive pancreatic precursor neoplasms.

Distinguishing Killian-Jamieson diverticulum from Zenker's diverticulum

BACKGROUND

Killian-Jamieson diverticulum, which is a relatively rare pharyngoesophageal diverticulum, is difficult to distinguish from Zenker's diverticulum. Because major points of the relevant surgical procedures for these two entities differ, it is important to make an accurate diagnosis. We herein report a case of Killian-Jamieson diverticulum initially diagnosed as Zenker's diverticulum.

CASE PRESENTATION

A 56-year-old man complaining of discomfort during swallowing was diagnosed with pharyngoesophageal diverticulum. He was initially diagnosed with Zenker's diverticulum before surgery, but the diverticulum actually arose from the left side of the esophageal wall, at the level of the cricoid cartilage and below the cricopharyngeal muscle. We therefore ultimately diagnosed this case as Killian-Jamieson diverticulum during surgery, and were able to preserve the muscle above the diverticulum, which would normally have to be cut when treating a case of Zenker's diverticulum.

CONCLUSION

To make an accurate diagnosis, clinical and surgical findings are important to consider, including the location of the diverticulum and the relationship between the diverticula and cricopharyngeal muscles or between the diverticula, thyroid cartilage and cricoid cartilage.

TWIST1 is a prognostic factor for neoadjuvant chemotherapy for patients with resectable pancreatic cancer: a preliminary study

Recent advances in the development of chemotherapies have helped improve the prognosis of pancreatic ductal adenocarcinoma (PDAC). However, predicting factors for the outcomes of chemotherapies (either gemcitabine or S-1) have not yet been established. We analyzed the expression of 4 major epithelial-to-mesenchymal transition-inducing transcription factors in 38 PDAC patients who received adjuvant chemotherapy after radical resection to examine the association with patients' prognoses. The TWIST1-positive group showed a significantly poorer prognosis than the TWIST1-negative group for both the relapse-free survival (median survival time [MST] of 8.9 vs. 18.5 months, P = 0.016) and the overall survival (MST of 15.2 vs. 33.4 months, P = 0.023). A multivariate analysis revealed that TWIST1 positivity was an independent prognostic factor for a poor response to adjuvant chemotherapies (hazard ratio 2.61; 95% confidence interval 1.10-6.79; P = 0.029). These results suggest that TWIST1 can be utilized as an important poor prognostic factor for radically resected PDAC patients with adjuvant chemotherapy, potentially including neoadjuvant therapy using these agents.

Distinguishing Killian–Jamieson diverticulum from Zenker’s diverticulum

Background

Killian–Jamieson diverticulum, which is a relatively rare pharyngoesophageal diverticulum, is difficult to distinguish from Zenker’s diverticulum. Because major points of the relevant surgical procedures for these two entities differ, it is important to make an accurate diagnosis. We herein report a case of Killian–Jamieson diverticulum initially diagnosed as Zenker’s diverticulum.

Case presentation

A 56-year-old man complaining of discomfort during swallowing was diagnosed with pharyngoesophageal diverticulum. He was initially diagnosed with Zenker’s diverticulum before surgery, but the diverticulum actually arose from the left side of the esophageal wall, at the level of the cricoid cartilage and below the cricopharyngeal muscle. We therefore ultimately diagnosed this case as Killian–Jamieson diverticulum during surgery, and were able to preserve the muscle above the diverticulum, which would normally have to be cut when treating a case of Zenker’s diverticulum.

Conclusion

To make an accurate diagnosis, clinical and surgical findings are important to consider, including the location of the diverticulum and the relationship between the diverticula and cricopharyngeal muscles or between the diverticula, thyroid cartilage and cricoid cartilage.

[A Case of an Elderly Patient Who Underwent Conversion Resection for Pancreatic Cancer with Positive Peritoneal Cytology]

We report a case of an elderly patient, 82 years-old, with initially-unresectable pancreatic head cancer, who successfully underwent complete resection of the primary lesion after systemic chemotherapy for 6 months. The patient had a history of pancreatic body-tail resection for intraductal papillary mucinous carcinoma in 2005. In 2020, a routine examination revealed an increased CA19-9 value of 1,958 U/mL and showed a pancreatic head tumor of 35 mm on CT images. Finally, the tumor was pathologically diagnosed as pancreatic cancer by a biopsied sample. Although CT images showed no distant metastasis, peritoneal lavage cytology was indicated as positivity(H0P0CY1)in the staging laparoscopy. We implanted a peritoneal port and introduced systemic chemotherapy of gemcitabine and nab-paclitaxel combination therapy. This treatment for 6 months induced tumor shrinkage to 30 mm on the CT image, normalized CA19-9 value to 22.6 U/mL, and negative cytology in the collected lavage fluid from the peritoneal port. The patient's general condition was maintained even after the chemotherapy and the lavage cytology was pathologically diagnosed as negative(H0P0CY0)in the repeated staging laparoscopy, therefore we decided to perform pancreaticoduodenectomy as a conversion surgery. The patient was discharged on the 21st postoperative day with an uneventful course and underwent adjuvant chemotherapy of S-1 for 6 months. No recurrence was found in 8 months after the surgery. In such a case of the selected elderly patient with a maintained general condition, it is feasible to undergo multimodal treatments including conversion surgery for an initially-unresectable pancreatic cancer with positive peritoneal cytology.

Early tumor shrinkage as a predictor of survival in patients with locally advanced pancreatic cancer treated with modified FOLFIRINOX or gemcitabine plus nab-paclitaxel combination therapy: An exploratory analysis of JCOG1407

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Background: Early tumor shrinkage (ETS) has been reported as a prognostic predictor of chemotherapy for colorectal cancer. However, few studies have examined the potential of ETS in chemotherapy for pancreatic cancer. Herein, we evaluated whether ETS could be a prognostic predictor in patients treated with modified FOLFIRINOX (5-fluorouracil, leucovorin, irinotecan, and oxaliplatin) or GnP (gemcitabine plus nab-paclitaxel) for locally advanced pancreatic cancer (LAPC), as an exploratory analysis of JCOG1407, a randomized phase II selection design trial comparing modified FOLFIRINOX and GnP for LAPC. Methods: Of 126 patients enrolled in JCOG1407, 112 with measurable lesions were included in this exploratory analysis. ETS was defined as a ≥ 20% reduction in tumor diameter compared with baseline at the initial imaging assessment 6–10 weeks after initiating chemotherapy. Patients were divided into two cohorts based on their ETS status as described above: the ETS cohort that achieved ETS and the non-ETS cohort that failed to achieve ETS. The impact of ETS on overall survival (OS) was compared using multivariable Cox regression analysis in (ⅰ) the modified FOLFIRINOX group, (ⅱ) the GnP group, and (ⅲ) the overall population. Results: Herein, we included 55 patients in the modified FOLFIRINOX group and 57 in the GnP group. Notably, 14 (25.5%) and 24 (42.1%) patients achieved ETS in the modified FOLFIRINOX and GnP groups, respectively. In the modified FOLFIRINOX group, the median OS in the ETS and non-ETS cohorts was 2.5 and 1.7 years, respectively; the adjusted hazard ratio (HR) of the ETS to the non-ETS cohort for OS was 0.37 (95% confidence interval [CI], 0.15-0.93). In the GnP group, the median OS in the ETS and non-ETS cohorts was 2.0 and 1.7 years, respectively; the adjusted HR of the ETS to the non-ETS cohort for OS was 0.51 (95% CI, 0.26-1.01). In the overall population, the median OS in the ETS and non-ETS cohorts was 2.3 and 1.7 years, respectively; the adjusted HR of the ETS to the non-ETS cohort for OS was 0.45 (95% CI, 0.27-0.75). Conclusions: We noted a trend toward increased survival in patients who achieved ETS, suggesting that ETS may be a prognostic predictor in patients with LAPC treated with modified FOLFIRINOX or GnP.

Syndrome of inappropriate secretion of antidiuretic hormone after total proctocolectomy for ulcerative colitis

We report a case of the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) after total proctocolectomy followed with ileal pouch-anal anastomosis (TPC-IPAA) for ulcerative colitis (UC). The patient was a 46-year-old woman. She was diagnosed with UC of pancolitis in 2000. High grade dysplasia was detected in the transverse colon after a surveillance colonoscopy in 2021. She underwent laparoscopy-assisted TPC-IPAA. On the sixth postoperative day, she had a decreased level of consciousness that worsened on the following day. Her laboratory data showed a serum sodium level of 108 mEq/L and the plasma osmolality was 234 mOsm/kg. We did not find any other abnormalities in the laboratory examination that could cause hyponatremia. Computed tomography scan showed no central nervous system disturbances such as a pituitary tumor, antidiuretic hormone-producing tumors, or pulmonary diseases. The patient was diagnosed with Syndrome of inappropriate secretion of antidiuretic hormone (SIADH) caused by surgical invasion. We started to administer 3% sodium chloride slowly to improve the hyponatremia. Her serum sodium level became normal and stable. Although it is rare for SIADH to be caused by abdominal surgery, if hyponatremia is observed after surgery, the possibility of postoperative SIADH should be considered.