The efficacy of wrapping with polyglycolic acid mesh and fibrin glue in preventing clinically relevant pancreatic fistula after minimally invasive distal pancreatectomy (WRAP Study): study protocol for a multicenter randomized controlled trial in Japan.

BACKGROUND: Postoperative pancreatic fistula (POPF) continues to be the most common complication after distal pancreatectomy (DP). Recent advancements in surgical techniques have established minimally invasive distal pancreatectomy (MIDP) as the standard treatment for various conditions, including pancreatic cancer. However, MIDP has not demonstrated a clear advantage over open DP in terms of POPF rates, indicating the need for additional strategies to prevent POPF in MIDP. This trial (WRAP study) aims to evaluate the efficacy of wrapping the pancreatic stump with polyglycolic acid (PGA) mesh and fibrin glue in preventing clinically relevant (CR-) POPF following MIDP. METHODS: This multicenter, randomized controlled trial will include patients scheduled for laparoscopic or robotic DP for tumors in the pancreatic body and/or tail. Eligible participants will be centrally randomized into either the control group (Group A) or the intervention group (Group B), where the pancreatic stump will be reinforced by PGA mesh and fibrin glue. In both groups, pancreatic transection will be performed using a bioabsorbable reinforcement-attached stapler. A total of 172 patients will be enrolled across 14 high-volume centers in Japan. The primary endpoint is the incidence of CR-POPF (International Study Group of Pancreatic Surgery grade B/C). DISCUSSION: The WRAP study will determine whether the reinforcement of the pancreatic stump with PGA mesh and fibrin glue, a technique whose utility has been previously debated, could become the best practice in the era of MIDP, thereby enhancing its safety. TRIAL REGISTRATION: This trial was registered with the Japan Registry of Clinical Trials on June 15, 2024 (jRCTs032240120).

Preoperative chemotherapy with Gemcitabine for pancreatic cancer causes zinc deficiency.

OBJECTIVES: The aim of this study was to investigate how preoperative chemotherapy affected the serum zinc concentrations in patients with pancreatic cancer (PC). METHODS: Two hundreds and thirty-one patients with PC who underwent pancreatectomy at our department from 2013 to 2019 were enrolled in this study and measured for the serum zinc concentrations before pancreatectomy. Patient characteristics, course of treatment, and laboratory data were analyzed. RESULTS: One hundred thirty-five patients underwent upfront pancreatectomy and 58 received preoperative Gemcitabine + S1 (GEM + S1) and 29 received Gemcitabine + nab-Paclitaxel (GEM + nab-PTX). Comparing the serum zinc concentrations before and after preoperative treatment, it was found to decrease after treatment with statistical difference (79.3 µg/dl vs. 68.7 µg/dl, p < 0.001). The result was consistent with the investigation for both the patients who received GEM + S1 and those who received GEM + nab-PTX (p = 0.019, p < 0.001, respectively). CONCLUSIONS: The preoperative chemotherapy consistently reduced the serum zinc concentrations in the PC patients, regardless of their regimen such as GEM + S1 and GEM + nab-PTX. Monitoring the serum zinc concentration and appropriate zinc supplementation may be essential for PC patients undergoing preoperative chemotherapy and pancreatectomy.

Deep learning predicts the 1-year prognosis of pancreatic cancer patients using positive peritoneal washing cytology.

Peritoneal washing cytology (CY) in patients with pancreatic cancer is mainly used for staging; however, it may also be used to evaluate the intraperitoneal status to predict a more accurate prognosis. Here, we investigated the potential of deep learning of CY specimen images for predicting the 1-year prognosis of pancreatic cancer in CY-positive patients. CY specimens from 88 patients with prognostic information were retrospectively analyzed. CY specimens scanned by the whole slide imaging device were segmented and subjected to deep learning with a Vision Transformer (ViT) and a Convolutional Neural Network (CNN). The results indicated that ViT and CNN predicted the 1-year prognosis from scanned images with accuracies of 0.8056 and 0.8009 in the area under the curve of the receiver operating characteristic curves, respectively. Patients predicted to survive 1 year or more by ViT showed significantly longer survivals by Kaplan-Meier analyses. The cell nuclei found to have a negative prognostic impact by ViT appeared to be neutrophils. Our results indicate that AI-mediated analysis of CY specimens can successfully predict the 1-year prognosis of patients with pancreatic cancer positive for CY. Intraperitoneal neutrophils may be a novel prognostic marker and therapeutic target for CY-positive patients with pancreatic cancer.

GFPT2 expression is induced by gemcitabine administration and enhances invasion by activating the hexosamine biosynthetic pathway in pancreatic cancer.

Our previous studies revealed a novel link between gemcitabine (GEM) chemotherapy and elevated glutamine-fructose-6-phosphate transaminase 2 (GFPT2) expression in pancreatic cancer (PaCa) cells. GFPT2 is a rate-limiting enzyme in the hexosamine biosynthesis pathway (HBP). HBP can enhance metastatic potential by regulating epithelial-mesenchymal transition (EMT). The aim of this study was to further evaluate the effect of chemotherapy-induced GFPT2 expression on metastatic potential. GFPT2 expression was evaluated in a mouse xenograft model following GEM exposure and in clinical specimens of patients after chemotherapy using immunohistochemical analysis. The roles of GFPT2 in HBP activation, downstream pathways, and cellular functions in PaCa cells with regulated GFPT2 expression were investigated. GEM exposure increased GFPT2 expression in tumors resected from a mouse xenograft model and in patients treated with neoadjuvant chemotherapy (NAC). GFPT2 expression was correlated with post-operative liver metastasis after NAC. Its expression activated the HBP, promoting migration and invasion. Treatment with HBP inhibitors reversed these effects. Additionally, GFPT2 upregulated ZEB1 and vimentin expression and downregulated E-cadherin expression. GEM induction upregulated GFPT2 expression. Elevated GFPT2 levels promoted invasion by activating the HBP, suggesting the potential role of this mechanism in promoting chemotherapy-induced metastasis.

Laparoscopic excision of accessory spleen for recurrent autoimmune hemolytic anemia after splenectomy: a case report.

BACKGROUND: Splenectomy is indicated in cases of autoimmune hemolytic anemia (AIHA), which are refractory to medical management. In post-splenectomy, there exists a theoretical risk of AIHA recurrence, especially if an accessory spleen undergoes compensatory hypertrophy. In this context, we present a unique case of recurrent AIHA managed through laparoscopic excision of the accessory spleen (LEAS). CASE PRESENTATION: A 60-year-old male underwent laparoscopic splenectomy (LS) for AIHA refractory to standard medical therapies. Following the surgery, there was a marked improvement in hemolytic anemia symptoms, and oral steroid therapy was terminated 7 months post-LS. Nonetheless, a year after the LS, the patient exhibited a marked decline in hemoglobin levels, dropping to a concerning 5.8 g/dl, necessitating the reintroduction of oral steroids. A subsequent contrast-enhanced computed tomography (CT) scan unveiled an enlarged accessory spleen. The patient then underwent LEAS, during which the accessory spleen, obscured within adipose tissue, proved challenging to visualize laparoscopically. This obstacle was surmounted utilizing intraoperative ultrasonography (US), enabling successful excision of the accessory spleen. The post-surgical period progressed without complications, and the steroid dosage was reduced to one-twelfth of its initial preoperative quantity. CONCLUSIONS: Recurrent AIHA can be instigated by post-splenectomy compensatory hypertrophy of the accessory spleen. Ensuring comprehensive splenic tissue excision is crucial in AIHA management to obviate recurrent stemming from hypertrophic remnants. In scenarios of AIHA recurrence tied to an enlarged accessory spleen, LEAS stands as a viable and effective therapeutic modality.

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

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

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 ß-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.

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.

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.

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 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.

Negative prognostic impact of sarcopenia before and after neoadjuvant chemotherapy for pancreatic cancer.

OBJECTIVES: To elucidate the prognostic impact of sarcopenia before and after neoadjuvant chemotherapy (NAC) for pancreatic cancer (PC). METHODS: We retrospectively studied 75 consecutive PC patients who underwent neoadjuvant gemcitabine plus S-1 combination therapy followed by pancreatectomy between 2008 and 2016. According to the skeletal muscle volume index (SMI), the patients were divided into the muscle attenuation group (MAG) and normal group (NG) before or after NAC. Prognostic factors for overall survival (OS) were analyzed by Cox proportional hazards models. RESULTS: The MAG showed significantly poorer OS than the NG before and after NAC. Pre-NAC, median OS was 20.0 months in the MAG versus 49.0 months in the NG (p = 0.006). Post-NAC, median OS was 21.3 months in the MAG versus 48.8 months in the NG (p = 0.014). Multivariate analysis, excluding muscle attenuation after NAC because of confounding factors and lower hazard ratio (2.08, 95% confidence interval: 1.14-3.78, p = 0.016) than that before NAC (2.14, 1.23-3.70, p = 0.007) by univariate analysis, revealed the following independent prognostic factors: muscle attenuation pre-NAC (2.25, 1.26-4.05, p = 0.007); borderline resectability (1.96, 1.04-3.69, p = 0.038); operative blood loss (2.60, 1.38-4.88, p = 0.003); and distant metastasis (3.31, 1.40-7.82, p = 0.006). CONCLUSIONS: Sarcopenia before and after NAC for PC is suggested to be a poor prognostic factor, with a stronger impact before than after NAC.

Pancreaticoduodenectomy for pancreatic head cancer with cavernous transformation of the portal vein: a case report.

BACKGROUND: Cavernous transformation of the portal vein (CTPV) due to extrahepatic portal vein obstruction is a rare vascular anomaly. Since its symptoms usually appear in childhood, most of the adult cases are detected unexpectedly with other diseases. Only a few reports have described surgical difficulties in patients with CTPV. We report a case of pancreatic head cancer with CTPV in a patient who underwent pancreaticoduodenectomy. CASE PRESENTATION: A 77-year-old man with epigastric and back pain was referred to our hospital. Computed tomography revealed a tumor in the pancreatic head and a CTPV near the hepatic hilum. CTPV consisted of two main collateral vessels connected by multiple surrounding small vessels. Also, portal vein obstruction was observed near the hepatic hilum, which was far from the pancreatic head tumor. After confirming that there was no distant metastasis by a thorough whole-body search, we performed a pancreaticoduodenectomy following neoadjuvant chemotherapy. During the operation, we carefully manipulated the area of the CTPV and omitted lymph node dissection in the hepatoduodenal ligament to prevent massive venous bleeding and intestinal congestion. Pancreaticoduodenectomy was performed without any intraoperative complications and the postoperative course was uneventful. Complete tumor resection was histologically confirmed. CONCLUSION: Although pancreaticoduodenectomy for patients with CTPV involves many surgical difficulties, we successfully performed it by determining specific treatment strategies tailored to the patient and following careful and delicate surgical procedures.

Distribution of Radioactive Cesium during Wild Boar Meat Processing.

ABSTRACT: Wild boar meat containing radioactive cesium (Cs) of approximately 1,000 Bq/kg (134Cs+137Cs) was processed into bacon, sausage, and ham. To understand the concentration and quantity change of radioactive Cs, the processing factor (Pf) and food processing retention factor (Fr) were calculated. The radioactive Cs quantity in the meat did not reduce during smoking. The dehydration-related meat mass reduction during smoking without decrease of radioactive Cs led to Cs condensation in the bacon compared with the raw rib meat before processing, resulting in a Pf of 1.18. Soaking in liquid, such as pickling in liquid and desalting or boiling in water, effectively removed radioactive Cs by leakage into water. Therefore, the Fr value of the boiled ham produced from a loin meat block through three liquid-soaking processes was 0.27. The Pf value of the boiled ham was 0.30 due to meat block mass reduction after boiling as a result of dehydration, along with protein thermal denaturation-related muscle tissue shrinkage. The steamed ham Fr value was 0.53, because the removal of radioactive Cs was less efficient by steaming than by boiling. The Pf value of the steamed ham was 0.54, almost the same as the Fr value, because the mass decrease rate was the same as the radioactive Cs decrease rate by steaming. The Fr and the Pf values of the boiled sausage, whose processing did not include soaking in the pickling liquid, were 0.64 and 0.62, respectively. Steaming the sausage meat did not remove radioactive Cs during the dehydration-related mass reduction, leading to Fr and Pf values of 1.01 and 1.17, respectively. This study found that processing into boiled ham was the most effective measure for reducing radioactive Cs quantity and concentration in raw meat. Processing into bacon and steamed sausage showed no Cs quantity reduction, with the moisture loss resulting in Cs condensation compared with the raw material.

Laparoscopic and robot-assisted surgery for adult congenital biliary dilatation achieves favorable short-term outcomes without increasing the risk of late complications.

PURPOSE: Minimally invasive surgery (MIS) is the optimal treatment for congenital biliary dilatation (CBD), but few studies on adults have been reported. We compared the postoperative outcomes of MIS with those of open surgery (OS) in adult patients with CBD. METHODS: The subjects of this retrospective study were 36 adult patients who underwent surgery for CBD. We compared the postoperative outcomes of 20 patients who underwent laparoscopic (n = 15) or robotic (n = 5) surgery with those of 16 patients who underwent OS. RESULTS: MIS was associated with a significantly higher rate of type I (p < 0.001), significantly less blood loss (p < 0.001), a significantly lower rate of internal stents (p = 0.048), significantly longer operation times (p = 0.009), and a significantly shorter postoperative hospital stay (p = 0.007) than OS. The postoperative outcomes of MIS for type I CBD were similar to those of the whole cohort. There were no significant differences in late complications between the groups. The robotic procedure had a significantly shorter operative time than laparoscopic surgery for hepaticojejunostomy (HJ; p = 0.029). CONCLUSIONS: MIS achieved favorable short-term outcomes without compromising mid-term outcomes compared to OS and is appropriate for adult patients with CBD. Robotic HJ may be more ideal than its laparoscopic counterpart.

Probiotic-related bacteremia after major hepatectomy for biliary cancer: a report of two cases.

BACKGROUND: Probiotics have been reported to be beneficial for the prevention of postoperative complications and are often used during the perioperative period. Among the probiotic-related adverse events, bacteremia is rare. Here, we report two cases of probiotic-related bacteremia after major hepatectomy for biliary cancer. CASE PRESENTATION 1: A 74-year-old man was referred to our hospital to be treated for gallbladder cancer. Neoadjuvant chemotherapy, two courses of gemcitabine plus S-1 combination therapy, was administered. Extended right hepatectomy with caudate lobectomy, extrahepatic bile duct resection and biliary reconstruction were performed 3 weeks after chemotherapy. Probiotics, Clostridium butyricum (C. butyricum) MIYAIRI 588, were administered 6 days before surgery and continued after surgery. Sepsis of unknown origin occurred 17 days after surgery and developed into septic shock. C. butyricum was detected in blood cultures at postoperative day 26 and 45. After stopping the probiotic agent, C. butyricum was undetectable in the blood cultures. The patient died due to an uncontrollable sepsis 66 days after surgery. CASE PRESENTATION 2: A 63-year-old man with diabetes mellitus whose past history included total colectomy, papillectomy, and Frey's operation at the age of 19, 34 and 48, respectively, was referred to our hospital to be treated for perihilar cholangiocarcinoma. Extended left hepatectomy with caudate lobectomy, extrahepatic bile duct resection and reconstruction of bile duct were performed. Probiotics were administered during the perioperative period. Combined probiotics that included lactomin, amylolytic bacillus and C. butyricum, were given before surgery. C. butyricum MIYAIRI 588 was given after surgery. Sepsis occurred 16 days after surgery and developed to respiratory failure 8 days later. Blood culture at postoperative day 25 revealed Enterococcus faecalis and C. butyricum. After the probiotics were stopped at postoperative day 27, C. butyricum was not detected in the blood culture. The general condition improved with intensive care. The patient was transferred to another hospital for rehabilitation at postoperative day 156. CONCLUSION: It should be noted that the administration of probiotics in severe postoperative complications can lead to probiotic-related bacteremia.

Ral GTPase-activating protein regulates the malignancy of pancreatic ductal adenocarcinoma.

The small GTPases RalA and RalB are members of the Ras family and activated downstream of Ras. Ral proteins are found in GTP-bound active and GDP-bound inactive forms. The activation process is executed by guanine nucleotide exchange factors, while inactivation is mediated by GTPase-activating proteins (GAPs). RalGAPs are complexes that consist of a catalytic α1 or α2 subunit together with a common ß subunit. Several reports implicate the importance of Ral in pancreatic ductal adenocarcinoma (PDAC). However, there are few reports on the relationship between levels of RalGAP expression and malignancy in PDAC. We generated RalGAPß-deficient PDAC cells by CRISPR-Cas9 genome editing to investigate how increased Ral activity affects malignant phenotypes of PDAC cells. RalGAPß-deficient PDAC cells exhibited several-fold higher Ral activity relative to control cells. They had a high migratory and invasive capacity. The RalGAPß-deficient cells grew more rapidly than control cells when injected subcutaneously into nude mice. When injected into the spleen, the RalGAPß-deficient cells formed larger splenic tumors with more liver metastases, and unlike controls, they disseminated into the abdominal cavity. These results indicate that RalGAPß deficiency in PDAC cells contributes to high activities of RalA and RalB, leading to enhanced cell migration and invasion in vitro, and tumor growth and metastasis in vivo.

Increased neutrophil-lymphocyte ratio predicts recurrence in patients with well-differentiated pancreatic neuroendocrine neoplasm based on the 2017 World Health Organization classification.

BACKGROUND: The prognostic values of inflammation-based markers in well-differentiated pancreatic neuroendocrine neoplasms, diagnosed according to the new 2017 World Health Organization classification, have remained unclear. Therefore, we assessed the ability to predict the recurrence of such markers after curative resection in patients with these neoplasms. METHODS: Circulating/systemic neutrophil-lymphocyte, monocyte-lymphocyte, platelet-lymphocyte, and platelet-white cell ratios were evaluated in 120 patients who underwent curative resection for well-differentiated pancreatic neuroendocrine neoplasms without synchronous distant metastasis between 2001 and 2018. Recurrence-free-survival and overall survival were compared using Kaplan-Meier analysis and log-rank tests. Univariate or multivariate analyses, using a Cox proportional hazards model, were used to calculate hazard ratios with 95% confidence intervals. RESULTS: Univariate analysis demonstrated that preoperative neutrophil-lymphocyte ratio, tumor size, European Neuroendocrine Tumor Society TMN classification, 2017 World Health Organization classification, and venous invasion were associated with recurrence. The optimal preoperative neutrophil-lymphocyte ratio cut-off value was 2.62, based on receiver operating characteristic curve analysis. In multivariate analysis, a higher preoperative neutrophil-lymphocyte ratio (HR = 3.49 95% CI 1.05-11.7; P = 0.042) and 2017 World Health Organization classification (HR = 8.81, 95% CI 1.46-168.2; P = 0.015) were independent recurrence predictors. CONCLUSIONS: The circulating/systemic neutrophil-lymphocyte ratio is a useful and convenient preoperative prognostic marker of recurrence in patients with well-differentiated pancreatic neuroendocrine neoplasm based on the 2017 World Health Organization classification.

Stomatin­like protein 2 induces metastasis by regulating the expression of a rate­limiting enzyme of the hexosamine biosynthetic pathway in pancreatic cancer.

Stomatin­like protein 2 (SLP­2) is associated with poor prognosis in several types of cancer, including pancreatic cancer (PC); however, the molecular mechanism of its involvement remains elusive. The present study aimed to elucidate the role of this protein in the development of PC. Human PC cell lines AsPC­1 and PANC­1 were transfected by a vector expressing SLP­2 shRNA. Analyses of cell proliferation, migration, invasion, chemosensitivity, and glucose uptake were conducted, while a mouse xenograft model was used to evaluate the functional role of SLP­2 in PC. Immunohistochemical analysis was retrospectively performed on human tissue samples to compare expression between the primary site (n=279) and the liver metastatic site (n=22). Furthermore, microarray analysis was conducted to identify the genes correlated with SLP­2. In vitro analysis demonstrated that cells in which SLP­2 was suppressed exhibited reduced cell motility and glucose uptake, while in vivo analysis revealed a marked decrease in the number of liver metastases. Immunohistochemistry revealed that SLP­2 was increased in liver metastatic sites. Microarray analysis indicated that this protein regulated the expression of glutamine­fructose­6­phosphate transaminase 2 (GFPT2), a rate­limiting enzyme of the hexosamine biosynthesis pathway. SLP­2 contributed to the malignant character of PC by inducing liver metastasis. Cell motility and glucose uptake may be induced via the hexosamine biosynthesis pathway through the expression of GFPT2. The present study revealed a new mechanism of liver metastasis and indicated that SLP­2 and its downstream pathway could provide novel therapeutic targets for PC.

Novel candidate factors predicting the effect of S-1 adjuvant chemotherapy of pancreatic cancer.

The collagen gel droplet-embedded drug sensitivity test (CD-DST) was revealed to be useful for predicting the effect of S-1 adjuvant chemotherapy for pancreatic ductal adenocarcinoma (PDAC). However, collection of an adequate number of PDAC cells is difficult due to the surrounding fibroblasts. Thus, the aim of this study was to discover novel biomarkers to predict chemosensitivity based on the CD-DST results. Proteomics analysis was performed using liquid chromatography tandem mass spectrometry (LC-MS/MS). Candidate proteins were validated in patients with 5-FU CD-DST results via immunohistochemistry (IHC). The relationships between the candidate proteins and the effect of the adjuvant S-1 were investigated via IHC. Among the 2696 proteins extracted by LC-MS/MS, C1TC and SAHH could accurately predict the CD-DST results. Recurrence-free survival (RFS) was significantly improved in the IHC-positive group compared with the IHC-negative group in both factors. The negative group did not show a significant difference from the group that did not receive S-1. The double-positive group was associated with significantly prolonged RFS compared to the no adjuvant chemotherapy group. C1TC and SAHH have been shown to be useful biomarkers for predicting 5-FU sensitivity as a substitute for the CD-DST in adjuvant chemotherapy for PDAC.