Reduction of butyrate-producing bacteria in the gut microbiome of Japanese patients with pancreatic cancer.

BACKGROUND: The incidence of pancreatic cancer is on the rise, and its prognosis remains poor. Recent reports have established a link between the gut and oral microbiome and pancreatic cancer. However, the intricacies of this association within the Japanese population remain unclear. In this study, we investigated the gut and oral microbiomes of Japanese patients with pancreatic cancer, comparing them with those of healthy individuals. METHODS: We recruited 30 patients with untreated pancreatic cancer and 18 healthy controls at Kyoto University Hospital (2018-2022). We performed a comprehensive 16S rRNA gene sequencing to analyze their gut and oral microbiomes. RESULTS: Analysis revealed that the diversity of the gut and oral microbiomes of patients with pancreatic cancer was reduced compared to that of the healthy controls. Specifically, we observed an increase in the genus Streptococcus in both the gut and oral microbiomes and a significant decrease in several butyrate-producing bacteria in fecal samples. Moreover, bacteria such as Streptococcus mitis and Holdemanella biformis were present in pancreatic cancer tissues, suggesting that they might influence the carcinogenesis and progression of pancreatic cancer. CONCLUSIONS: The gut and oral microbiome differed between patients with pancreatic cancer and healthy controls, with a notable decrease in butyrate-producing bacteria in the gut microbiome of the patients. This suggests that there may be a distinct microbial signature associated with pancreatic cancer in the Japanese population. Further studies are required to elucidate the microbiome's causal role in this cancer and help develop prognostic markers or targeted therapies.

Inhibition of dopamine receptor D1 signaling promotes human bile duct cancer progression via WNT signaling.

Bile duct cancer (BDC) frequently invades the nerve fibers, making complete surgical resection difficult. A single tumor mass contains cells of variable malignancy and cell-differentiation states, with cancer stem cells (CSCs) considered responsible for poor clinical outcomes. This study aimed to investigate the contribution of autosynthesized dopamine to CSC-related properties in BDC. Sphere formation assays using 13 commercially available BDC cell lines demonstrated that blocking dopamine receptor D1 (DRD1) signaling promoted CSC-related anchorage-independent growth. Additionally, we newly established four new BDC patient-derived organoids (PDOs) and found that blocking DRD1 increased resistance to chemotherapy and enabled xenotransplantation in vivo. Single-cell analysis revealed that the BDC PDO cells varied in their cell-differentiation states and responses to dopamine signaling. Further, DRD1 inhibition increased WNT7B expression in cells with bile duct-like phenotype, and it induced proliferation of other cell types expressing Wnt receptors and stem cell-like signatures. Reagents that inhibited Wnt function canceled the effect of DRD1 inhibition and reduced cell proliferation in BDC PDOs. In summary, in BDCs, DRD1 is a crucial protein involved in autonomous CSC proliferation through the regulation of endogenous WNT7B. As such, inhibition of the DRD1 feedback signaling may be a potential treatment strategy for BDC.

Preoperative Endoscopic Minor Papilla Sphincterotomy for Pancreas Divisum in a Patient with Pancreatic Cancer Who Underwent Laparoscopic Distal Pancreatectomy.

BACKGROUND: Pancreas divisum (PD) is a congenital anomaly that occurs due to failure of fusion of the dorsal and ventral pancreatic ductal systems.1-3 In PD, pancreatic juice drains mainly through the minor papilla via the dorsal duct, leading to high intraductal pressure, which can cause pancreatitis.1-3 We report a case of PD that underwent preoperative decompression using endoscopic minor papilla sphincterotomy (EMPS) before laparoscopic distal pancreatectomy (LDP) for pancreatic cancer.3 METHODS: The patient was a 74-year-old woman with pancreatic tail cancer, measuring 35 mm in size, in PD with an entirely dilated dorsal duct, implying high, intraductal pressure caused by minor papillary dysfunction. We performed EMPS to prevent postoperative pancreatitis and pancreatic fistula before LDP using a left-posterior approach, as previously described.4 As the pancreatic transection margin was positive for high-grade pancreatic intraepithelial neoplasia on intraoperative pathology, an additional resection of the pancreatic head to the right side of the portal vein was performed after the liberation of the gastroduodenal artery with both the dorsal and ventral pancreatic ducts ligated and divided. RESULTS: The operative time was 421 min, and blood loss was 70 mL. The postoperative course was uneventful, with no evidence of pancreatitis or pancreatic fistula. The patient was discharged on postoperative Day 10. Postoperative computed tomography revealed reduced dilatation of the dorsal duct. CONCLUSIONS: Preoperative EMPS may be effective in preventing pancreatic fistula after LDP in patients with PD.

Propensity Score Matching Analysis of the Safety of Completion Total Pancreatectomy for Remnant Pancreatic Tumors Versus that of Initial Total Pancreatectomy for Primary Pancreatic Tumors.

BACKGROUND: The safety and feasibility of completion total pancreatectomy (TP) for remnant pancreatic neoplasms remain controversial and are rarely compared with that of initial TP. Thus, we aimed to compare the safety of these two procedures inducing a pancreatic state. METHODS: Patients who underwent TP for pancreatic neoplasms between 2006 and 2018 at our institution were included in this study. Tumor pathologies were classified into three subgroups according to survival curves. We used 1:1 propensity score matching (PSM) to analyze age, sex, Charlson Comorbidity Index, and tumor stage. Finally, we analyzed the primary outcome Clavien-Dindo classification (CDC) grade, risks of other safety-related outcomes, and the survival rate of patients with invasive cancer. RESULTS: Of 54 patients, 16 underwent completion TP (29.6%) and 38 (70.4%) underwent initial TP. Before PSM analysis, age and Charlson Comorbidity Index were significantly higher, and T category and stage were significantly lower for the completion TP group. Upon PSM analysis, these two groups were equivalent in CDC grade [initial TP vs. completion TP: 71.4% (10/14) vs. 78.6% (11/14); p = 0.678] and other safety-related outcomes. Additionally, while the overall survival and recurrence-free survival of patients with invasive cancer were not significantly different between these two groups, the T category and stage tended to be remarkably severe in the initial TP group. CONCLUSIONS: PSM analysis for prognostic factors showed that completion TP and initial TP have similar safety-related outcomes that can be used as a decision-making reference in the surgery of pancreatic tumors.

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.

Impact of liver volumetric regeneration on survival outcomes in patients with hepatocellular carcinoma after major hepatectomy.

PURPOSE: Prognostic value of liver volumetric regeneration (LVR) in patients with hepatocellular carcinoma (HCC) who undergo major hepatectomy remains unknown. The aim of this study was to investigate the impact of LVR on long-term outcomes in these patients. METHODS: Data of 399 consecutive patients with HCC who underwent major hepatectomy between 2000 to 2018 were retrieved from a prospectively maintained institutional database. The LVR-index was defined as the relative increase in liver volume from 7 days to 3 months (RLV3m/RLV7d, where RLV3m and RLV7d is the remnant liver volume around 3 months and postoperative 7 days after surgery). The optimal cut-off value was determined using the median value of LVR-index. RESULTS: A total of 131 patients were eligible in this study. The optimal cut off value of LVR-index was 1.194. The 1-, 3-, 5- and 10-year overall survival (OS) rate of patients in the high LVR-index group were significantly better compared to those in the low LVR-index group (95.5%, 84.8%, 75.4% and 49.1% vs. 95.4%, 70.2%, 56.4%, and 19.9%, p = 0.002). Meanwhile, there was no significant difference with regards to time to recurrence between the two groups (p = 0.607). Significance of LVR-index for OS was retained after adjusting for known prognostic factors (p = 0.002). CONCLUSION: In patients with HCC undergoing major hepatectomy, LVR-index may serve as a prognostic indicator for OS.

[Simultaneous living donor liver transplantation and pancreatoduodenectomy for an extensive cholangiocarcinoma with primary sclerosing cholangitis: a case report].

The treatment of choice for a resectable hilar cholangiocarcinoma is hepatectomy. Alternative treatment for unresectable cases includes liver transplantation;however, curative surgery is hindered by a distal cholangiocarcinoma extension into the intrapancreatic duct. Herein, we present a case of simultaneous living donor liver transplantation and pancreaticoduodenectomy for an extensive cholangiocarcinoma that is associated with primary sclerosing cholangitis, involving the perihilar and intrapancreatic duct. The treatment strategy involved neoadjuvant chemotherapy and radiation therapy, an exploratory laparoscopy and laparotomy for accurate staging, en-bloc whole bile duct and hepatoduodenal ligament resection, portal vein reconstruction with an interposition graft, and arterial reconstruction with the middle colic artery. The patient was discharged 122 days postoperatively although she suffered from postoperative ascites and delayed gastric emptying. Simultaneous living donor liver transplantation and pancreatoduodenectomy should be considered as treatment options for advanced cholangiocarcinoma.

Impact of neoadjuvant intensity-modulated radiation therapy on borderline resectable pancreatic cancer with arterial abutment; a prospective, open-label, phase II study in a single institution.

BACKGROUND: Borderline resectable pancreatic cancer (BRPC) is a category of pancreatic cancer that is anatomically widely spread, and curative resection is uncommon with upfront surgery. Intensity-modulated radiation therapy (IMRT) is a form of radiation therapy that delivers precise radiation to a tumor while minimizing the dose to surrounding normal tissues. Here, we conducted a phase 2 study to estimate the curability and efficacy of neoadjuvant chemoradiotherapy using IMRT (NACIMRT) for patients with BRPC with arterial abutment (BRPC-A). METHODS: A total of 49 BRPC-A patients were enrolled in this study and were treated at our hospital according to the study protocol between June 2013 and March 2021. The primary endpoint was microscopically margin-negative resection (R0) rates and we subsequently analyzed safety, histological effect of the treatment as well as survivals among patients with NACIMRT. RESULTS: Twenty-nine patients (59.2%) received pancreatectomy after NACIMRT. The R0 rate in resection patients was 93.1% and that in the whole cohort was 55.1%. No mortality was encountered. Local therapeutic effects as assessed by Evans classification showed good therapeutic effect (Grade 1, 3.4%; Grade 2a, 31.0%; Grade 2b, 48.3%; Grade 3, 3.4%; Grade 4, 3.4%). Median disease-free survival was 15.5 months. Median overall survival in the whole cohort was 35.1 months. The only independent prognostic pre-NACIMRT factor identified was serum carbohydrate antigen 19-9 (CA19-9) > 400 U/ml before NACIMRT. CONCLUSIONS: NACIMRT showed preferable outcome without significant operative morbidity for BRPC-A patients. NACIMRT contributes to good local tumor control, but a high initial serum CA19-9 implies poor prognosis even after neoadjuvant treatment. TRIAL REGISTRATION: UMIN-CTR Clinical Trial: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000011776 Registration number: UMIN000010113. Date of first registration: 01/03/2013.

Preoperative risk stratification of lymph node metastasis for non-functional pancreatic neuroendocrine neoplasm: An international dual-institutional study.

BACKGROUND: /Objectives: Although the presence of lymph node metastasis (LNM) defines malignant potential, preoperative prediction of LNM has not been established for non-functional pancreatic neuroendocrine neoplasm (NF-PNEN). We sought to develop a prediction system using only preoperatively available factors that would stratify the risk of LNM for NF-PNEN. METHODS: We retrospectively reviewed patients who underwent R0/1 resection of NF-PNEN at Kyoto University (2007-2019) and the University of California, San Francisco (2010-2019). Risk stratification of LNM was developed using preoperative factors by the logistic regression analysis. Long-term outcomes were compared across the risk groups. RESULTS: A total of 131 patients were included in this study. Lymph nodes were pathologically examined in 116 patients, 23 (20%) of whom had LNM. Radiological tumor size [1.5-3.5 cm (odds ratio: 13.5, 95% confidence interval: 1.77-398) and >3.5 cm (72.4, 9.06-2257) against ≤1.5 cm], <50% cystic component (8.46 × 10^6, 1.68 × 10^106-), and dilatation of main pancreatic duct ≥5 mm (31.2, 3.94-702) were independently associated with LNM. When patients were classified as the low-risk (43 patients), intermediate-risk (44 patients), and high-risk groups (29 patients), proportions of LNM differed significantly across the groups (0%, 14%, and 59%, respectively). Recurrence-free survival (RFS) of the low- and intermediate-risk groups were significantly better than that of the high-risk group (5-year RFS rates of 92.2%, 85.4%, and 47.1%, respectively). CONCLUSIONS: The prediction system using preoperative radiological factors stratifies the risk of LNM for NF-PNEN. This stratification helps to predict malignant potential and determine the surgical procedure and necessity of regional lymphadenectomy.

The Benefits of Fibrinolysis Combined with Venous Systemic Oxygen Persufflation (VSOP) in a Rat Model of Donation after Circulatory Death and Orthotopic Liver Transplantation.

Organ shortage has led to the increasing utilization of livers retrieved from donors after circulatory death (DCD). These pre-damaged organs are susceptible to further warm ischemia and exhibit minimal tolerance for cold storage. The aim was thus to examine the effects of fibrinolysis combined with Venous Systemic Oxygen Persufflation (VSOP) on the preservation of DCD livers in vivo. Livers of male Lewis rats were explanted after 45 min of warm ischemia, cold-stored for 18 h, and transplanted into a recipient animal. Livers were left untreated or underwent either VSOP or fibrinolysis via Streptokinase (SK) or received combined SK and VSOP. Combined treatment exhibited improved microvascular flow at 168 h (p = 0.0009) and elevated microperfusion velocity at 24 h post-transplantation (p = 0.0007). Combination treatment demonstrated increased portal venous flow (PVF) at 3 and 24 h post-transplantation (p = 0.0004, p < 0.0001), although SK and VSOP analogously achieved increases at 24 h (p = 0.0036, p = 0.0051). Enzyme release was decreased for combination treatment (p = 0.0002, p = 0.0223) and lactate dehydrogenase (LDH) measurements were lower at 24 h post-transplantation (p = 0.0287). Further supporting findings have been obtained in terms of serum cytokine levels and in the alterations of endothelial injury markers. The combination treatment of SK + VSOP might provide improved organ integrity and viability and may therefore warrant further investigation as a potential therapeutic approach in the clinical setting of DCD.

Impact of vascular abnormality on contrast-enhanced CT and high C-reactive protein levels on postoperative pancreatic hemorrhage after pancreaticoduodenectomy: A multi-institutional, retrospective analysis of 590 consecutive cases.

BACKGROUND: /Objectives: This study aimed to elucidate the efficacy of CT findings and perioperative characteristics to predict post-pancreatectomy hemorrhage (PPH): a critical complication after pancreaticoduodenectomy. METHODS: The records of 590 consecutive patients who underwent pancreaticoduodenectomy at three institutes between 2012 and 2018 were included. The presence of a vascular wall abnormality or ascites with high density (vascular abnormality) on postoperative day (POD) 5-10 contrast-enhanced CT (early CT), perioperative characteristics, and any PPH or pseudoaneurysm formation (PPH events) were analyzed through a multivariate analysis. RESULTS: PPH events occurred in 48 out of 590 patients (8%). The vascular abnormality on early CT and the C-reactive protein (CRP) value on POD 3 were independent risk factors for PPH events after POD5 (vascular abnormality: odds ratio 6.42, p = 0.001; CRP on POD 3: odds ratio 1.17, p = 0.016). The sensitivity of vascular abnormality for PPH events was 24% (7/29), and the positive predictive value was 30% (7/23). The combination of vascular abnormality and a high CRP value (≥15.5 mg/dL) on postoperative day 3 had a higher positive predictive value of 64% (7/11) than the vascular abnormality alone. None of the seven PPH events that occurred more than one month after surgery were foreseen via early CT. CONCLUSION: The combination of vascular abnormality and high CRP value was associated with increasing risk of PPH events after pancreaticoduodenectomy, but the low sensitivity of early CT must be noted as an important shortcoming. The normal findings on early CT could not eliminate the risk of late PPH.

Risk factors for short recurrence-free survival after resection of pancreatic neuroendocrine tumor (PanNET) liver metastases: which patients should undergo resection?

Background: In the treatment of metastatic pancreatic neuroendocrine tumors (PanNETs), surgical resection is the first choice if curative resection is expected. However, most patients develop recurrence after resection of liver metastasis. Because one of the benefits of resection is to gain a tumor-free period for the patients, it is important to identify which patients achieve longer recurrence-free survival (RFS) by resection. In this study, the clinicopathological factors associated with RFS after resection of metastatic PanNETs in the liver were evaluated to identify the patient group that is suitable for resection.Methods: Consecutively diagnosed patients with PanNET liver metastasis with resection at our hospital from January 2000 to July 2019 were evaluated. A total of 26 metastatic PanNET patients with primary liver resections were evaluated. The median follow-up time was 48.3 months.Results: There were 18 NET recurrences of the total 26 resections, with a median RFS of 17.9 months. Independent risk factors for short RFS were a high Ki67 index (p = .009) and the number of resected tumors (p = .045). When the cut-off value for the Ki67 index was 5.0% and that for the number of resected tumors was 6, Ki67 > 5.0% tumors had shorter RFS (4.9 months vs. 38.2 months p = .006), and patients with tumors > = 7 tumors had shorter RFS (4.7 months vs. 27.5 months p = .001).Conclusions: These findings indicate that good candidates for resection of metastatic tumors of PanNETs could be patients with low Ki67 tumors and a small number of metastatic tumors.

Left-posterior approach for artery-first en bloc resection in laparoscopic distal pancreatectomy for left-sided pancreatic cancer.

PURPOSE: We describe a "left-posterior approach" in which the important steps in laparoscopic distal pancreatectomy (LDP) for left-sided pancreatic cancer are accomplished in the direction caudal and dorsal to the pancreas. METHODS: The patients who underwent LDP with a left-posterior approach at our hospital from January 2016 to April 2020 were reviewed to evaluate the short-term postoperative outcomes. In LDP, we first dissected retroperitoneal tissues above the left renal vein and superior mesenteric artery, yielding the mobilization of the pancreatic body widely. Then, the splenic artery was divided behind the ventrally lifted pancreas as an artery-first approach. The regional lymphadenectomy was performed in an en bloc manner consecutively in the same operative field. The neck of the pancreas was transected with a linear stapler after mobilization of the spleen. RESULTS: In nine patients (five men and four women) aged 76 years (range: 64-82 years), the operative time was 398 min (276-482 min) with the estimated blood loss of 40 ml (0-80 ml). No patients developed grade B/C pancreatic fistula or delayed gastric emptying. Postoperative complications classified as grade III in the Clavien-Dindo classification occurred in one patient (abdominal abscess). The pathology confirmed R0 resection in all patients who had pancreatic cancer (n = 5), IPMNs (n = 3), and high-grade pancreatic intraepithelial neoplasia (PanIN) (n = 1). The number of retrieved lymph nodes was 35 (11-49). CONCLUSION: The procedure with a left-posterior approach is a rational surgical technique in LDP for left-sided pancreatic cancer.

Combination of postoperative C-reactive protein value and computed tomography imaging can predict severe pancreatic fistula after pancreatoduodenectomy.

BACKGROUND: Recent management after pancreatoduodenectomy recommends either omission of prophylactic drainage or early removal. This potentially makes the diagnosis of postoperative pancreatic fistula (POPF) difficult because the diagnosis is based on the amylase value of drain effluent. The aim of this study was to determine if severe POPF could be predicted independent of drainage information. METHODS: Records of consecutive patients who underwent pancreatoduodenectomy between 2012 and 2018 were included for further analysis. The presence of a peripancreatic collection (PC) on routine postoperative (day7) computed tomography (early CT) and perioperative characteristics were analyzed. RESULTS: PC appeared in 82/211 patients (39%) and was associated with clinically relevant POPF (p < 0.001). The C-reactive protein (CRP) on postoperative day5 was a good predictor of severe POPF (needing interventional therapy or Grade C) (area under the receiver operating characteristics curve, 0.802; 95% confidence interval, 0.702-0.875). Presence of a PC and a high CRP value were independent risk factors for severe POPF following multivariate analysis. The combination of CRP<5.0 mg/dL on postoperative day 5 and the absence of a PC had 98% negative predictive value. CONCLUSION: The combination of CRP measurement and PC evaluation by early CT was useful in predicting severe POPF after pancreatoduodenectomy.

Older Donor Age Is a Risk Factor for Negative Outcomes After Adult Living Donor Liver Transplantation Using Small-for-Size Grafts.

Adult-to-adult living donor liver transplantation (ALDLT) using small-for-size grafts (SFSGs), ie, a graft with a graft-to-recipient weight ratio (GRWR) <0.8%, has been a challenge that should be carefully dealt with, and risk factors in this category are unclear. Therefore, we aimed to examine the risk factors and outcomes of ALDLT using SFSGs over a 13-year period in 121 patients who had undergone their first ALDLT using SFSGs. Small-for-size syndrome (SFSS), early graft loss, and 1-year mortality were encountered in 21.6%, 14.9%, and 18.4% of patients, respectively. By multivariate analysis, older donor age (≥45 years) was an independent risk factor for SFSS (odds ratio [OR], 4.46; P = 0.004), early graft loss (OR, 4.11; P = 0.02), and 1-year mortality (OR, 3.76; P = 0.02). Child-Pugh C class recipients were associated with a higher risk of SFSS development (P = 0.013; OR, 7.44). Despite no significant difference between GRWR categories in the multivariate outcome analysis of the whole population, in the survival analysis of the 2 donor age groups, GRWR <0.6% was associated with significantly lower 1-year survival than the other GRWR categories in the younger donor group. Moreover, in the high final portal venous pressure (PVP) group (>15 mm Hg), younger ABO-compatible donors showed 100% 1-year survival with a significant difference from the group of other donors. Older donor age was an independent risk factor for SFSS, early graft loss, and 1-year mortality after ALDLT using SFSGs. GRWR should not be <0.6%, and PVP modulation is indicated when grafts from older or ABO-incompatible donors are used.

Predictive value of the Ki67 index for lymph node metastasis of small non-functioning pancreatic neuroendocrine neoplasms.

BACKGROUND: We evaluated the clinicopathological factors associated with lymph node metastasis in patients with non-functioning pancreatic neuroendocrine neoplasms (PanNENs), focusing on the risk factors and range of lymph node metastasis for tumors ≤ 2 cm in diameter. METHODS: The subjects of this study were patients with PanNENs consecutively diagnosed at our hospital between January, 2000 and June, 2018. We analyzed 69 patients who underwent R0 resection of a non-functioning sporadic PanNEN with no distant metastasis, as well as 43 patients with tumors ≤ 20 mm in radiological diameter. RESULTS: Nineteen patients (27.5%), including 7 (16.3%) with a small PanNEN, had lymph node metastasis. A large radiological diameter, a high Ki67 index, and cyst formation correlated significantly with positive lymph node metastasis. In patients with tumors ≤ 20 mm in diameter, a high Ki67 index correlated significantly with lymph node metastasis. When we set the cut-off Ki67 index as 3.3%, 2 of 43 patients had lymph node metastasis. Tumors in the uncinate process readily metastasized to the region around the superior mesenteric artery. CONCLUSIONS: These findings suggest that a high Ki67 index indicates a risk of lymph node metastasis for tumors ≤ 20 mm in diameter and that lymphadenectomy should be performed in the region spatially adjacent to the primary tumor.

The Impact of a Nitric Oxide Synthase Inhibitor (L-NAME) on Ischemia⁻Reperfusion Injury of Cholestatic Livers by Pringle Maneuver and Liver Resection after Bile Duct Ligation in Rats.

The Pringle maneuver (PM) has been widely used to control blood loss during liver resection. However, hepatic inflow occlusion can also result in hepatic ischemia-reperfusion injury (IRI), especially in patients with a cholestatic, fibrotic, or cirrhotic liver. Here we investigate a nitric oxide synthase (NOS) inhibitor N-Nitroarginine methyl ester (L-NAME) on IRI after the PM and partial hepatectomy of cholestatic livers induced by bile duct ligation (BDL) in rats. Control group (non-BDL/no treatment), BDL + T group (BDL/L-NAME treatment) and BDL group (BDL/no treatment) were analyzed. Cholestasis was induced by BDL in the L-NAME and BDL group and a 50% partial hepatectomy with PM was performed. L-NAME was injected before PM in the BDL + T group. Hepatocellular damage, portal venous flow, microcirculation, endothelial lining, and eNOS, iNOS, interleukin (IL)-6, and transforming growth factor-ß (TGF-ß) were evaluated. Microcirculation of the liver in the BDL + T group tended to be higher. Liver damage and apoptotic index were significantly lower and Ki-67 labeling index was higher in the BDL + T group while iNOS and TGF-ß expression was decreased. This was corroborated by a better preserved endothelial lining. L-NAME attenuated IRI following PM and improved proliferation/regeneration of cholestatic livers. These positive effects were considered as the result of improved hepatic microcirculation, prevention of iNOS formation, and TGF-ß mRNA upregulation.

Comparison of Recurrence Between Pancreatic and Duodenal Neuroendocrine Neoplasms After Curative Resection: A Single-Institution Analysis.

BACKGROUND: The primary site of a neuroendocrine neoplasms (NEN) around the head of the pancreas is sometimes difficult to assess before resection, and the characteristics of the primary site around this region have not been elucidated for recurrence after curative resection. In this study, the clinicopathologic characteristics of pancreatic NEN (PanNEN) and duodenal NEN (DuNEN) were evaluated, and the risk factors as well as the recurrence types after resection were investigated. METHODS: Consecutively diagnosed NEN patients at the authors' hospital from January 2000 to July 2016 were evaluated in this study. For 117 PanNEN patients and 31 non-ampullary DuNEN patients, R0 resection was achieved. The median follow-up period was 8.1 years. RESULTS: In this study, 27 PanNEN patients (23.1%) had recurrences, with a median disease-free survival (DFS) of 133 months, whereas 11 DuNEN patients (35.5%) had recurrences, with a median DFS of 156 months. The PanNEN patients tended to have primary recurrence in the liver (85.2%), followed by lymph nodes (11.1%). The independent risk factors for short DFS were lymph node metastasis at resection (p = 0.001) and microvascular invasion (p = 0.048). In contrast, the DuNEN patients were likely to have lymph node metastasis (81.8%). The independent risk factors for short DFS were lymph node metastasis at resection (p = 0.003) and large diameter (p = 0.013). CONCLUSIONS: Most initial recurrences of PanNEN occurred in the liver, whereas those of DuNEN appeared in lymph nodes, suggesting that proper diagnosis of the primary site and appropriate imaging methods for surveillance after resection are necessary.