Impact of intratumoral microbiome on tumor immunity and prognosis in human pancreatic ductal adenocarcinoma.

BACKGROUND: Recent evidence suggests that the presence of microbiome within human pancreatic ductal adenocarcinoma (PDAC) tissue potentially influences cancer progression and prognosis. However, the significance of tumor-resident microbiome remains unclear. We aimed to elucidate the impact of intratumoral bacteria on the pathophysiology and prognosis of human PDAC. METHODS: The presence of intratumoral bacteria was assessed in 162 surgically resected PDACs using quantitative polymerase chain reaction (qPCR) and in situ hybridization (ISH) targeting 16S rRNA. The intratumoral microbiome was explored by 16S metagenome sequencing using DNA extracted from formalin-fixed paraffin-embedded tissues. The profile of intratumoral bacteria was compared with clinical information, pathological findings including tumor-infiltrating T cells, tumor-associated macrophage, fibrosis, and alterations in four main driver genes (KRAS, TP53, CDKN2A/p16, SMAD4) in tumor genomes. RESULTS: The presence of intratumoral bacteria was confirmed in 52 tumors (32%) using both qPCR and ISH. The 16S metagenome sequencing revealed characteristic bacterial profiles within these tumors, including phyla such as Proteobacteria and Firmicutes. Comparison of bacterial profiles between cases with good and poor prognosis revealed a significant positive correlation between a shorter survival time and the presence of anaerobic bacteria such as Bacteroides, Lactobacillus, and Peptoniphilus. The abundance of these bacteria was correlated with a decrease in the number of tumor-infiltrating T cells positive for CD4, CD8, and CD45RO. CONCLUSIONS: Intratumoral infection of anaerobic bacteria such as Bacteroides, Lactobacillus, and Peptoniphilus is correlated with the suppressed anti-PDAC immunity and poor prognosis.

Risk factors for adverse outcomes at various phases of endoscopic ultrasound-guided treatment of pancreatic fluid collections: Data from a multi-institutional consortium.

OBJECTIVES: No comprehensive study has examined short- and long-term adverse outcomes of endoscopic ultrasound (EUS)-guided treatment of pancreatic fluid collections (PFCs) including walled-off necrosis (WON) and pseudocysts. METHODS: In a multi-institutional cohort of 357 patients receiving EUS-guided treatment of PFCs (228 with WON and 129 with pseudocysts), we examined PFC type-specific risk factors for procedure-related adverse events (AEs), clinical failure, and recurrence. Odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (CIs) were computed using the logistic and Cox regression models, respectively, adjusting for potential confounders. RESULTS: Adverse events were observed predominantly in WON, and risk factors were WON extension to the pelvis (OR 2.49; 95% CI 1.00-6.19) and endoscopic necrosectomy (OR 5.15; 95% CI 1.61-16.5). Risk factors for clinical failure in WON treatment included higher Charlson Comorbidity Index (OR for ≥3 vs. ≤2, 2.58; 95% CI 1.05-6.35), extension to the pelvis (OR 3.63; 95% CI 1.57-8.43), nonuse of a lumen-apposing metal stent (OR 2.88; 95% CI 1.10-7.54), and percutaneous drainage (OR 3.73; 95% CI 1.27-10.9). Patients with pseudocysts extending to the paracolic gutter and the need for more than two endoscopic/percutaneous procedures had ORs for clinical failure of 5.28 (95% CI 1.10-25.3) and 5.52 (95% CI 1.61-18.9), respectively. Pseudocysts requiring the multigateway approach were associated with a high risk of recurrence (HR 4.00; 95% CI 1.11-11.6). CONCLUSION: The adverse outcomes at various phases of EUS-guided PFC treatment may be predictable based on clinical parameters. Further research is warranted to optimize treatment strategies for high-risk patients.

Association of PNPLA3 SNP With the Development of HBV-related Hepatocellular Carcinoma.

BACKGROUND/AIM: Concomitant nonalcoholic fatty liver disease (NAFLD)/hepatic steatosis (HS) is suggested to increase the risk of hepatocellular carcinoma (HCC) in hepatitis virus B (HBV)-infected patients. Patatin-like phospholipase domain-containing 3 (PNPLA3) rs738409 gene single-nucleotide polymorphism (SNP) is well-known to be associated with the development of NAFLD/HS; however, it is still unclear whether this SNP is related to the development of HCC in HBV-infected patients. PATIENTS AND METHODS: We investigated a total of 202 HBV-infected patients who received percutaneous liver biopsy, and simultaneously assessed biopsy-proven HS, insulin resistance, and the PNPLA3 SNP status. We further investigated the relationships of these factors with the development of HCC in HBV-infected patients. RESULTS: Most of the enrolled cases (196/202: 97.0%) were non-cirrhotic patients. One hundred seventy-three patients (85.6%) received antiviral therapy. A Kaplan-Meier analysis showed that the incidence of HCC development in patients with HS was higher than that in patients without HS (p<0.01). An increased homeostasis model assessment as an index of insulin resistance (HOMA-IR) value (≥1.6) was associated not only with the presence of HS (p<0.0001) but also with the development of HCC (p<0.01). The PNPLA3 rs738409 SNP was also associated with the presence of HS (p<0.01) and the development of HCC (p<0.05) in HBV-infected patients. CONCLUSION: In addition to HS and IR, PNPLA3 rs738409 SNP was suggested to be associated with the development of HCC in Japanese patients with HBV infection.

A case of delayed pancreatic fistula after covered self-expandable metallic stent deployment for pancreatic head cancer.

A 69-year-old man was referred to our hospital with obstructive jaundice. A tumor with poor contrast enhancement was found in the pancreatic head, but there was no evidence of pancreatic atrophy, irregular stenosis, or dilation of the main pancreatic duct. He was diagnosed with borderline resectable pancreatic cancer with distal malignant biliary obstruction. After plastic stent placement, serum bilirubin levels improved, and chemotherapy was started. However, he developed cholangitis; thus, the plastic stent was replaced with a covered self-expandable metallic stent. He subsequently developed a delayed pancreatic fistula due to main pancreatic duct disruption. An endoscopic nasopancreatic duct drainage tube was placed to bridge the main pancreatic duct disruption after removing the covered self-expandable metallic stent. In addition, endoscopic ultrasound-guided transmural drainage was performed for the infected fluid collection caused by the pancreatic fistula, and the clinical symptoms quickly improved. This case presents the possibility of a delayed pancreatic fistula due to self-expandable metallic stent deployment. The need for considering such delayed complications when placing self-expanding metallic stents is highlighted.

Metastasis of Hepatocellular Carcinoma in the Pouch of Douglas Successfully Treated by Radiation Therapy: A Case Report.

Metastasis of hepatocellular carcinoma (HCC) in the pouch of Douglas is relatively rare. A 65-year-old man with liver cirrhosis was admitted for detailed examination of a pelvic tumor. He had a previous history of ruptured HCC, and received emergent hemostasis with transcatheter arterial embolization followed by curative ablation. His blood tests showed an increase in des-gamma-carboxy prothrombin (DCP). Contrast-enhanced computed tomography (CE-CT) revealed a heterogeneously enhanced large pelvic tumor, but no additional tumorous lesions were detected in other organs, including the lungs, liver and abdominal lymph nodes. The colonoscopy showed compression by an extra-luminal/submucosal tumor, and computed tomography-guided percutaneous needle biopsy revealed that the pelvic tumor was metastasis of HCC. Because of the poor liver function, the solitary pelvic tumor was treated with three-dimensional conformal radiation therapy (3D-CRT). The tumor size and the DCP value were markedly decreased after radiation therapy. Nine months later, occasional mild bloody stool due to radiation proctitis was observed; however, no serious side effects occurred. Our case suggests that radiation therapy may be a therapeutic option for a solitary metastatic lesion of HCC in the pouch of Douglas.

Early versus delayed interventions for necrotizing pancreatitis: A systematic review and meta-analysis.

Objectives: Interventions for necrotizing pancreatitis are generally postponed until 4 weeks after the onset of acute pancreatitis, but there remains controversy about whether we should always wait >4 weeks or can intervene early when necessary. This meta-analysis was conducted to evaluate treatment outcomes of necrotizing pancreatitis according to the cut-off defined in the revised Atlanta classification (≤4 vs. >4 weeks). Methods: Using PubMed, Web of Science, and the Cochrane database, we identified clinical studies published until March 2022 with data comparing outcomes of early and delayed interventions of necrotizing pancreatitis. We pooled data on adverse events, mortality, technical and clinical success rates, and needs for necrosectomy and open surgery, using the random-effects model. Results: We identified 11 retrospective studies, including 775 patients with early interventions and 725 patients with delayed interventions. Patients with early interventions tended to be complicated by organ failure. The rate of adverse events was comparable (OR 1.41, 95% CI 0.66-3.01; p = 0.38) but the rate of mortality was significantly higher (OR 1.70, 95% CI 1.21-2.40; p < 0.01) in early interventions. Technical success rates were similarly high but clinical success rates tended to be low (OR 0.39, 95% CI 0.15-1.00; p = 0.05) in early interventions, though not statistically significant. Pooled ORs for necrosectomy and open surgery were 2.14 and 1.23, respectively. Conclusions: Early interventions for necrotizing pancreatitis were associated with higher mortality rates and did not reduce adverse events or improve clinical success. However, our results should be confirmed in prospective studies.

Rapid transformation of branched pancreatic duct-derived intraductal tubulopapillary neoplasm into an invasive carcinoma: A case report.

BACKGROUND: Intraductal tubulopapillary neoplasm (ITPN) is a rare disease accounting for approximately 3% of all intraductal pancreatic tumors, with intraductal papillary mucinous neoplasm (IPMN) being one of the most common differential diagnoses. Both ITPN and IPMN display slow growth. A branched pancreatic duct type is commonly observed in IPMN, whereas ITPN derived from the branched pancreatic duct has been reported in a limited number of cases; hence, its pathogenesis remains unclear. CASE SUMMARY: Here, we present the case of a patient with ITPN localized in a branched pancreatic duct, with poorly controlled irritable bowel syndrome. A contrast-enhanced computed tomography scan of the abdomen incidentally revealed a 5-mm oligemic nodule-like change in the body of the pancreas. Endoscopic ultrasound (EUS) indicated a 10-mm hypoechoic mass without any cystic structures that had grown within 2 mo. EUS-guided fine needle aspiration was performed for definitive diagnosis, and the findings suggested ductal papillary carcinoma. Distal pancreatectomy was performed, and the tumor was pathologically diagnosed as ITPN with an invasive cancerous component, pT3N1aM0, pStage IIB (International Cancer Control, 8th edition). The patient underwent treatment with postoperative adjuvant chemotherapy (S-1 monotherapy); however, relapse was observed 1 year and 10 mo after surgical resection, and subsequent treatment involving a combination of chemotherapy and radiotherapy was administered. Maintenance therapy has since facilitated a stable disease state. CONCLUSION: Regardless of the microscopic size of the neoplasm, early diagnosis of ITPN with EUS-guided fine needle aspiration and surgical resection are crucial.

Diagnosis of hepatic steatosis based on ultrasound attenuation imaging is not influenced by liver fibrosis.

AIM: Recently, a new technique using attenuation imaging (ATI) was developed to diagnose hepatic steatosis. The aim of this study was to investigate whether ATI for the evaluation of hepatic steatosis is influenced by liver fibrosis. METHODS: A total of 328 patients with chronic liver disease were enrolled to study the associations between histological hepatic steatosis or liver fibrosis and ATI findings. The interaction between liver fibrosis and ATI was also analyzed. RESULTS: Median ATI values according to steatosis grade and fibrosis stage increased in line with the progression of liver steatosis (p < 0.001) and fibrosis (p < 0.05). However, in each steatosis grade, ATI values according to fibrosis stage were not significantly increased. In multiple regression analyses for assessment of the effect of their interaction, the p values for fibrosis stage, steatosis grade, and fibrosis stage × steatosis grade were 0.096, <0.001, and 0.077, respectively. Variance inflation factor values for fibrosis stage, steatosis grade, and fibrosis stage × steatosis grade were 1.079, 1.094, and 1.074, respectively. CONCLUSION: Attenuation imaging values are not influenced by liver fibrosis.

Clinical Characteristics of ICI-Related Pancreatitis and Cholangitis Including Radiographic and Endoscopic Findings.

The indications for immune checkpoint inhibitors (ICIs) have expanded to include carcinomas of various organs. However, as ICI therapy expands, the management of immune-related adverse events (irAEs) has become a problem. ICI-related pancreatitis and cholangitis are relatively rare irAEs. Although some patients with ICI-related pancreatitis and cholangitis are asymptomatic and do not require treatment, there have been reports of patients who did not respond to immunosuppressive therapy and died. Thus, the pathogenesis of ICI-related pancreatitis and cholangitis should be clarified immediately. Currently, the role of endoscopy in the diagnosis and treatment of inflammatory pancreatic and biliary duct diseases is becoming increasingly important. In this review, we summarize clinical characteristics as well as radiographic and endoscopic findings of ICI-related pancreatitis and cholangitis.

Possible Alterations in Appetite-related Molecules After the Elimination of Hepatitis C Virus.

BACKGROUND/AIM: Recent advances in antiviral treatment have achieved a sustained viral response (SVR) in over 95% of hepatitis C virus (HCV) infections. HCV elimination is suggested to improve several lifestyle-related factors; however, few studies have focused on dietary habit-/appetite-related factors. PATIENTS AND METHODS: HCV-infected patients who received Daclatasvir/Asnaprevir (DCV/ASV) therapy were enrolled, and the changes in appetite-related molecules after antiviral therapy were assessed with a multiple cytokine-measuring system. RESULTS: Among 119 HCV-infected patients who received DCV/ASV treatment, 104 (87.3%) achieved an SVR. In the SVR group, DCV/ASV treatment improved several liver-related variables at 24 weeks after the completion of therapy. In patients with an SVR, the values of glucagon-like peptide 1 (GLP-1) and leptin were significantly increased at 24 weeks after completing direct-acting antiviral therapy. However, no significant change was observed in non-SVR patients, regardless of the receipt of direct-acting antiviral treatment. CONCLUSION: Gastrointestinal hormones related to the dietary habit and/or appetite may be influenced by HCV elimination.

Modification of the ALBI-PLT Score for the Prediction of High-risk Varices.

BACKGROUND/AIM: A new scoring system [albumin-bilirubin-platelet (ALBI-PLT) score] was reported for identifying cirrhotic patients without high-risk varices (HRV), and patients with ALBI grade 1 (≤-2.60) and a platelet count over 150×109/l were shown to have a low risk of having HRV. The present study modified the cut-off values of the variables in the ALBI-PLT score. PATIENTS AND METHODS: Among a total of 338 patients with chronic liver diseases, possible cut-off values of the ALBI score and the platelet count were determined by analyzing the first-half group (training cohort: N=169) with the receiver operating characteristic (ROC) method. The utility of the determined values was evaluated in the second-half group (validation cohort: N=169) and total cohort (N=338). In addition, the utility of the modified cut-off values was evaluated in patients with compensated cirrhosis (cirrhotic cohort: N=87). RESULTS: Possible cut-off values of the ALBI score and platelet count were found to be -2.36 and 114×109/l, respectively. In the training cohort, these cut-off values provided a higher ratio of avoiding esophagogastroduodenoscopy than the original ALBI-PLT score (53.3% vs. 25.4%, p<0.01). Consistent results were observed in the validation cohort (28.4% vs. 15.4%, p<0.01), total cohort (40.8% vs. 20.4%, p<0.01), and cirrhotic cohort (32.2% vs. 11.5%, p<0.01). However, the missing ratio of patients with the HRV was not significantly increased in any cohort studied. CONCLUSION: Modification of the ALBI-PLT score may be useful for predicting patients without HRV.

Multiple Inflammatory Pseudotumors of the Liver Demonstrating Spontaneous Regression: A Case Report.

Inflammatory pseudotumor (IPT) of the liver is a rare benign disease. IPTs generally develop as solitary nodules, and cases with multiple lesions are uncommon. We herein report a case of multiple IPTs of the liver that spontaneously regressed. A 70-year-old woman with a 10-year history of primary biliary cholangitis and rheumatoid arthritis visited our hospital to receive a periodic medical examination. Abdominal ultrasonography revealed multiple hypoechoic lesions, with a maximum size of 33 mm, in the liver. Contrast-enhanced computed tomography revealed low-attenuation areas in the liver with mild peripheral enhancement at the arterial and portal phases. We first suspected metastatic liver tumors, but fluorodeoxyglucose positron emission tomography, magnetic resonance imaging and contrast-enhanced ultrasonography suggested the tumors to be inconsistent with malignant nodules. A percutaneous biopsy showed shedding of liver cells and abundant fibrosis with infiltration of inflammatory cells. Given these findings, we diagnosed the multiple tumors as IPTs. After careful observation for two months, the tumors almost vanished spontaneously. Physicians should avoid a hasty diagnosis of multiple tumors based solely on a few clinical findings, and a careful assessment with various imaging modalities should be conducted.

Endoscopic Ultrasound-Guided Gastroenterostomy for Afferent Loop Syndrome.

Afferent loop syndrome (ALS) is a mechanical obstruction of the afferent limbs after gastrectomy with gastrojejunostomy reconstruction. Patients with cancer recurrence require immediate and less invasive treatment because of their poor condition. Percutaneous transhepatic/transluminal drainage (PTD) and endoscopic enteral stenting offer reasonable palliative treatment for malignant ALS but are not fully satisfactory in terms of patient quality of life (QoL) and stent patency. Endoscopic ultrasound-guided gastroenterostomy (EUS-GE) using a lumen-apposing metal stent may address these shortcomings. Clinical data from 11 reports showed that all patients who had undergone EUS-GE had positive technical and clinical outcomes. The adverse event rate was 11.4%, including only mild or moderate abdominal pain, with no severe adverse events. Indirect comparative studies indicated that patients who had undergone EUS-GE had a significantly superior QoL, a higher clinical success rate, and a lower reintervention rate than those who had undergone PTD or endoscopic enteral stenting. Although the evidence is limited, EUS-GE may be considered as a first-line treatment for malignant ALS because it has better clinical outcomes than other less invasive treatments, such as PTD or endoscopic enteral stenting. Further prospective randomized control trials are necessary to establish EUS-GE as a standard treatment for ALS.

[Cystoid macular edema secondary to albumin-bound paclitaxel therapy for pancreatic cancer].

Cystoid macular edema (CME) is a rare adverse event induced by taxane-based chemotherapy. Here, we describe the case of a 71-year-old man who developed bilateral CME during treatment with nab-paclitaxel (nab-PTX) for unresectable pancreatic cancer. Two months after drug discontinuation, his vision improved, and there was significant reduction in the CME on optical coherence tomography. CME is an adverse event that can be treated with the early withdrawal of nab-PTX. Oncologists who use nab-PTX should be aware of this adverse event for timely patient referral to an ophthalmologist and appropriate treatment that would enable the preservation of the patient's visual acuity.

An Autopsy Case of Anaplastic Carcinoma of the Pancreas in a 39-Year-Old Woman that Developed from Hereditary Pancreatitis.

BACKGROUND Anaplastic carcinoma of the pancreas (ACP) is a rare type of cancer with an extremely poor prognosis. Hereditary pancreatitis is a rare autosomal-dominant disease. It progresses to chronic pancreatitis at a young age, increasing the risk of pancreatic cancer. CASE REPORT A 39-year-old woman was diagnosed with chronic pancreatitis at the age of 18 years. The patient was referred to our hospital for epigastralgia and jaundice. We identified a tumor mass at the head of the pancreas using contrast computed tomography (CT) and endoscopic ultrasound (EUS) of the abdomen. Tissue biopsy revealed ACP of the spindle cell type. We started the patient on combination chemotherapy using gemcitabine and nanoparticle albumin-bound (nab) -paclitaxel, but she died 1 month after her first visit. An autopsy revealed a mixture of tubular adenocarcinoma and anaplastic carcinoma. We performed genetic analysis using DNA samples from the biopsy tissues but did not find mutations in the PRSS1 and SPINK1 genes associated with hereditary pancreatitis. CONCLUSIONS The risk of pancreatic cancer generally increases in patients with hereditary pancreatitis after 50 years of age. However, in this case, the development of pancreatic cancer occurred at a younger age, suggesting the importance of early detection in such cases. Furthermore, this case suggests that EUS is a useful method for monitoring patients with hereditary pancreatitis and the diagnosis of ACP.