Impact of endoscopic ultrasound-guided tissue acquisition on prognosis and peritoneal lavage cytology in resectable or borderline resectable pancreatic ductal adenocarcinoma.

OBJECTIVES: This study aimed to evaluate the clinical impact of preoperative endoscopic ultrasound-guided tissue acquisition (EUS-TA) on the prognosis and incidence of positive peritoneal lavage cytology (PLC) during laparotomy or staging laparoscopy in patients with resectable (R) or borderline resectable (BR) pancreatic ductal adenocarcinoma (PDAC). METHODS: We retrospectively collected data from patients diagnosed with body and tail PDAC with/without EUS-TA at our hospital from January 2006 to December 2021. RESULTS: To examine the effect of EUS-TA on prognosis, 153 patients (122 in the EUS-TA group, 31 in the non-EUS-TA group) were analyzed. There was no significant difference in overall survival between the EUS-TA and non-EUS-TA groups after PDAC resection (P = 0.777). In univariate and multivariate analysis, preoperative EUS-TA was not identified as an independent factor related to overall survival after pancreatectomy [hazard ratio 0.96, 95 % confidence interval (CI) 0.54-1.70, P = 0.897]. Next, to examine the direct influence of EUS-TA on the results of PLC, 114 patients (83 in the EUS-TA group and 31 in the non-EUS-TA group) were analyzed. Preoperative EUS-TA was not statistically associated with positive PLC (odds ratio 0.73, 95 % CI 0.25-2.20, P = 0.583). After propensity score matching, overall survival and positive PLC were the same in both groups. CONCLUSIONS: EUS-TA had no negative impact on postoperative survival and PLC-positive rates in R/BR PDAC.

Maintenance steroid therapy is associated with decreased risk of malignancy and better prognosis of patients with autoimmune pancreatitis: A multicenter cohort study in Japan.

BACKGROUND/OBJECTIVES: The association between autoimmune pancreatitis (AIP) and pancreatic cancer (PC) remains controversial. This study aimed to clarify the long-term prognosis and risk of malignancies in AIP patients in Japan. METHODS: We conducted a multicenter retrospective cohort study on 1364 patients with type 1 AIP from 20 institutions in Japan. We calculated the standardized incidence ratio (SIR) for malignancies compared to that in the general population. We analyzed factors associated with overall survival, pancreatic exocrine insufficiency, diabetes mellitus, and osteoporosis. RESULTS: The SIR for all malignancies was increased (1.21 [95 % confidence interval: 1.05-1.41]) in patients with AIP. Among all malignancies, the SIR was highest for PC (3.22 [1.99-5.13]) and increased within 2 years and after 5 years of AIP diagnosis. Steroid use for ≥6 months and ≥50 months increased the risk of subsequent development of diabetes mellitus and osteoporosis, respectively. Age ≥65 years at AIP diagnosis (hazard ratio [HR] = 3.73) and the development of malignancies (HR = 2.63), including PC (HR = 7.81), were associated with a poor prognosis, whereas maintenance steroid therapy was associated with a better prognosis (HR = 0.35) in the multivariate analysis. Maintenance steroid therapy was associated with a better prognosis even after propensity score matching for age and sex. CONCLUSIONS: Patients with AIP are at increased risk of developing malignancy, especially PC. PC is a critical prognostic factor for patients with AIP. Although maintenance steroid therapy negatively impacts diabetes mellitus and osteoporosis, it is associated with decreased cancer risk and improved overall survival.

Intravenous injection of tumor extracellular vesicles suppresses tumor growth by reducing the regulatory T cell phenotype.

BACKGROUND: Colorectal cancer is a disease of unmet medical need. Although extracellular vesicles (EVs) have been implicated in anti-tumor responses, discrepancies were observed among studies. We analyzed the role of tumor-derived EVs (TEVs) in tumor progression in vivo by focusing on regulatory T (Treg) cells, which play essential roles in tumor development and progression. METHODS: A mouse model of colorectal cancer lung metastasis was generated using BALB/c mice by tail vein injection of the BALB/c colon adenocarcinoma cell line Colon-26. TEVs derived from Colon-26 and BALB/c lung squamous cell carcinoma ASB-XIV were retrieved from the culture media supernatants. A TEV equivalent to 10 µg protein was injected every other day for 2 weeks. RESULTS: Histology and immunohistochemistry studies revealed that lung tumors reduced in the Colon-26-EV group when compared to the phosphate-buffered saline (PBS) group. The population of CD4 + FoxP3 + cells in the lung was upregulated in the PBS group mice when compared to the healthy mice (P < 0.001), but was significantly downregulated in the Colon-26-EV group mice when compared to the PBS group mice (P < 0.01). Programmed cell death protein 1, glucocorticoid-induced TNFR-related protein, and CD69 expression in lung Treg cells were markedly upregulated in the PBS group when compared to the healthy mice, but downregulated in the Colon-26-EV group when compared to the PBS group. The changes in expression were dose-dependent for Colon-26-EVs. ASB-EVs also led to significantly downregulated Treg cell expression, although non-cancer line 3T3-derived EVs did not. CONCLUSION: Our study suggests that TEVs possess components for tumor suppression.

Survival impact of occult liver metastasis and peritoneal dissemination compared with radiologically defined distant organ metastasis in pancreatic ductal adenocarcinoma.

BACKGROUND: Characteristics and prognoses of patients with occult metastases (OM) of pancreatic ductal adenocarcinoma (PDAC) compared with radiologically defined metastases (RM) have been rarely reported. OBJECTIVE: We aimed to clarify the prognosis of OM compared with RM and to establish a treatment strategy for PDAC patients with OM. METHODS: This single-institution, retrospective study evaluated patients with unresectable PDAC between 2008 and 2018. OM was defined as abdominal metastasis that was detected by staging laparoscopy or open laparotomy but not in the initial assessment of radiological images. RESULTS: OM and RM were identified in 135 and 112 patients, respectively. Eastern Cooperative Oncology Group Performance Status (ECOG PS), neutrophil to lymphocyte ratio (NLR), tumor diameter, and rate of local unresectability were significantly lower in the OM group. Median overall survival (OS) of OM was significantly better than that of RM (13.0 vs 8.9 months, p < 0.001). In multivariate analysis of OS, ECOG PS ≥ 1 (HR 1.64, p = 0.009), NLR ≥5 (HR 1.97, p = 0.004), carbohydrate antigen (CA) 19-9 ≥1000 (HR 1.68, p = 0.001), tumor diameter ≥40 mm (HR 1.40, p = 0.027), conversion surgery (HR 0.12, p < 0.001), and multiple lines of chemotherapy (HR 0.38, p < 0.001) were independent predictors. However, type of metastasis (OM vs RM) not an independent predictor (HR 1.10, p = 0.590). CONCLUSION: The prognosis of PDAC with OM was relatively better than that with RM, but general and nutritional statuses, primary tumor size and CA19-9, conversion surgery and multiple lines of chemotherapy were independent predictors but not tumor burden.

Impact of neoadjuvant therapy on gut microbiome in patients with resectable/borderline resectable pancreatic ductal adenocarcinoma.

BACKGROUND: /Objectives: Effects of chemotherapy on gut microbiota have been reported in various carcinomas. The current study aimed to evaluate the changes in the gut microbiota before and after neoadjuvant chemotherapy (NAC) in patients with resectable (R) and borderline resectable (BR) pancreatic ductal adenocarcinoma (PDAC) and understand their clinical implications. METHODS: Twenty patients diagnosed with R/BR-PDAC were included in this study. Stool samples were collected at two points, before and after NAC, for microbiota analysis using 16S ribosomal RNA (16S rRNA) gene sequences. RESULTS: Of the 20 patients, 18 (90%) were treated with gemcitabine plus S-1 as NAC, and the remaining patients received gemcitabine plus nab-paclitaxel and a fluorouracil, leucovorin, irinotecan, and oxaliplatin combination. No significant differences were observed in the α- and ß-diversity before and after NAC. Bacterial diversity was not associated with Evans classification (histological grade of tumor destruction by NAC) or postoperative complications. The relative abundance of Actinobacteria phylum after NAC was significantly lower than that before NAC (P = 0.02). At the genus level, the relative abundance of Bifidobacterium before NAC in patients with Evans grade 2 disease was significantly higher than that in patients with Evans grade 1 disease (P = 0.03). Patients with Evans grade 2 lost significantly more Bifidobacterium than patients with Evans grade 1 (P = 0.01). CONCLUSIONS: The diversity of gut microbiota was neither decreased by NAC for R/BR-PDAC nor associated with postoperative complications. Lower incidence of Bifidobacterium genus before NAC may be associated with a lower pathological response to NAC.

The academic impact and value of an international online surgery lecture series.

Due to the worldwide travel restrictions caused by the 2019 coronavirus disease pandemic, many universities and students lost opportunities to engage in international exchange over the past 2 years. Teleconferencing systems have thus been developed to compensate for severe travel restrictions. Kansai Medical University in Japan and Vilnius University in Lithuania have a collaborative research and academic relationship. The two universities have been conducting an online joint international surgery lecture series for the medical students of both universities. Fifteen lectures were given from October 2021 to May 2022. The lectures focused on gastrointestinal surgery, gastroenterology, radiology, pathology, genetics, laboratory medicine, and organ transplantation. A survey of the attendees indicated that they were generally interested in the content and satisfied with attending this lecture series. Our efforts were successful in providing Japanese and Lithuanian medical students with the opportunity to engage in international exchange through lectures held in each other's countries.

Postprocedure serum amylase or lipase levels predict postendoscopic retrograde cholangiopancreatography pancreatitis: Meta-analysis of diagnostic test accuracy studies and utility assessment.

OBJECTIVES: We aimed to clarify the clinical utility of measuring serum pancreatic enzymes after endoscopic retrograde cholangiopancreatography (ERCP) for the purpose of predicting post-ERCP pancreatitis (PEP) by a meta-analysis of diagnostic test accuracy studies. METHODS: Studies on the prediction accuracy of PEP by serum amylase or lipase measured at 2, 3, and 4 h after ERCP were collected. A literature search was performed in PubMed and the Cochrane Library database for studies published between January 1980 and March 2023. The quality of individual studies was evaluated using the Quality Assessment of Diagnostic Accuracy Studies-2. Data were analyzed using Meta-DiSc 2.0 software. RESULTS: We searched the databases and identified 20 observational studies (12,313 participants). PEPs were defined according to criteria by Cotton or modified Cotton, revised Atlanta criteria, or the Japanese criteria. Meta-analysis of eight studies (4389 participants) showed a pooled sensitivity of 71.1% (95% confidence interval [CI] 56.1-82.5) and pooled specificity of 91.2% (95% CI 85.9-94.6) for the serum amylase cut-off value at 3 times the upper limit of normal (ULN). Another meta-analysis of five studies (1970 participants) showed a pooled sensitivity of 85.8% (95% CI 61.9-95.7) and pooled specificity of 85.3% (95% CI 81.9-88.1) for the serum lipase cut-off value at 3 times ULN. CONCLUSION: Despite a high risk of bias due to various reference standards, this updated meta-analysis and the utility assessment by a decision tree showed the utility of serum amylase or lipase levels more than 3 times ULN measured 2-4 h after ERCP for predicting PEP.

Recent progress on the treatment of type 1 autoimmune pancreatitis and IgG4-related disease.

IgG4-related disease (IgG4-RD) is a fibroinflammatory disorder recognized as a novel clinical entity with either synchronous or metachronous multiorgan involvement. Autoimmune pancreatitis (AIP) is classified into two types: type 1 AIP as a pancreatic manifestation of IgG4-RD and type 2 AIP with granulocytic epithelial lesion and occasional association with ulcerative colitis. Although the pathogenic mechanism still remains unclear, possible multipathogenic factors such as genetic factors, disease-specific or related antigens, and abnormal innate or adaptive immunity may be involved in the development of IgG4-RD. Many immunocytes including M2 macrophages, plasmablasts, B cells, and T-cells (Th2-CD4+T, follicular helper T-cells, and CD4+SLAMF7+cytotoxic T-cells) play important roles in the pathogenesis. Conventional induction and maintenance therapies with glucocorticoid or rituximab are recommended in all symptomatic patients with active IgG4-RD. In those at risk for irreversible damage in any organs, this should be done urgently, regardless of symptoms. As no randomized clinical trials other than glucocorticoid maintenance therapy for type 1 AIP have been performed, the comprehensive management for IgG4-RD has not been established yet. Targeted treatment approaches against the plasmablast to B cell lineage and the CD4+ SLAMF7+ cytotoxic T-cell seem to be promising for the future-directed treatment.

Long-term outcomes of patients with multifocal intraductal papillary mucinous neoplasm following pancreatectomy.

BACKGROUND: The decision to perform surgery is complicated by the presence of multifocal (MF) intraductal papillary mucinous neoplasms (IPMNs), which are characterized by two or more cysts located in different areas of the pancreas. OBJECTIVES: We aimed to establish a suitable treatment strategy and surgical indications in patients with MF-IPMNs. METHODS: This single-center retrospective study included patients with IPMNs who underwent pancreatic resection from 2006 to 2020. Patients with distant metastasis and patients with IPMNs of the main pancreatic duct were excluded from the analysis. RESULTS: After excluding 22 patients, 194 patients were included. One hundred thirteen patients (58.2%) had unifocal IPMNs, while 81 patients (41.8%) had MF-IPMNs. There were no significant differences in the 5-year disease-specific survival (DSS) rate (92.3% vs. 92.4%, p = 0.976) and the 5-year disease-free survival rate (88.6% vs. 86.5%, p = 0.461). The multivariate analysis identified high-risk stigmata, invasive carcinoma, and lymph node metastasis as independent predictors of DSS. The presence of cystic lesions in the pancreatic remnant was not a predictor of survival. Even in the MF-IPMN group, there were no significant differences in DSS when stratified by procedure (total pancreatectomy vs. segmental pancreatectomy, p = 0.268) or presence of cystic lesions in the pancreatic remnant (p = 0.476). The multivariate analysis identified lymph node metastasis as an independent predictor of DSS in the MF-IPMN group. CONCLUSIONS: In patients with MF-IPMNs, each cyst should be evaluated individually for the presence of features associated with malignancy.

Nationwide epidemiological survey of immunoglobulin G4-related disease with malignancy in Japan.

BACKGROUND AND AIM: To clarify the clinicoepidemiological characteristics of immunoglobulin G4 (IgG4)-related disease (IgG4-RD) with malignancy, a nationwide epidemiological survey was conducted. METHODS: Immunoglobulin G4-related disease patients with malignancy who had visited selected hospitals in Japan were surveyed. The study consisted of two stages: the number of IgG4-RD patients with malignancy was estimated by the first questionnaire and their clinicoepidemiological characteristics were assessed by the second questionnaire. RESULTS: The frequencies of autoimmune pancreatitis (AIP), IgG4-related sialadenitis, IgG4-related eye disease, IgG4-related kidney disease, and IgG4-related retroperitoneal fibrosis were 44.7%, 20.8%, 14.0%, 5.16%, and 5.12%, respectively. The overall prevalence of malignant disease in IgG4-RD cases was estimated to be 10 900 per 100 000 cases, which was significantly higher than that of malignant disease in the general population. The prevalence of malignant lymphoma in IgG4-RD cases was the highest and was estimated to be 1985 per 100 000 cases. IgG4-related kidney disease had the highest frequency of malignant disease (17.1%). In data from 200 patients, 61 (30.5%) cases of cancer were found 2 years or more before the IgG4-RD diagnosis, 92 cases (46%) during the 1 year preceding or following IgG4-RD diagnosis, and 62 cases of cancer (31%) 2 or more years following IgG4-RD diagnosis. CONCLUSIONS: The nationwide survey for IgG4-RD with malignancy in Japan showed that IgG4-RD may be related with malignant diseases.

High tumor budding predicts a poor prognosis in resected duodenal adenocarcinoma.

PURPOSE: Tumor budding is a histological characteristic defined as the presence of small clusters of cancer cells at the invasion front. Its significance in duodenal adenocarcinoma (DA) has not been fully described. METHODS: A single-center, retrospective study was conducted. Patients who underwent curative surgery for histologically diagnosed DA from January 2006 to December 2018 at Kansai Medical University Hospital were included. Tumor budding was counted per 0.785 mm2 and classified as low (0-4 buds), intermediate (5-9 buds), or high (≥ 10 buds). RESULTS: In total, 47 patients were included. The 5-year overall survival and relapse-free survival rates were 77% and 72%, respectively. High tumor budding was seen in 15 patients (32%). Excluding patients with superficial type (pT1) DA (n = 22), high tumor budding [hazard ratio (HR) 13.4, p = 0.028], regional lymph node metastasis (HR 19.9, p = 0.039), and adjuvant chemotherapy (HR 0.056, p = 0.036) were independent factors related to the overall survival in multivariate analyses. Distant metastases occurred significantly more often in patients who had high tumor budding than in others (p = 0.039). CONCLUSION: The data suggest that high tumor budding is a predictor of a poor prognosis in resected DA.

Variants That Affect Function of Calcium Channel TRPV6 Are Associated With Early-Onset Chronic Pancreatitis.

BACKGROUND & AIMS: Changes in pancreatic calcium levels affect secretion and might be involved in development of chronic pancreatitis (CP). We investigated the association of CP with the transient receptor potential cation channel subfamily V member 6 gene (TRPV6), which encodes a Ca2+-selective ion channel, in an international cohort of patients and in mice. METHODS: We performed whole-exome DNA sequencing from a patient with idiopathic CP and from his parents, who did not have CP. We validated our findings by sequencing DNA from 300 patients with CP (not associated with alcohol consumption) and 1070 persons from the general population in Japan (control individuals). In replication studies, we sequenced DNA from patients with early-onset CP (20 years or younger) not associated with alcohol consumption from France (n = 470) and Germany (n = 410). We expressed TRPV6 variants in HEK293 cells and measured their activity using Ca2+ imaging assays. CP was induced by repeated injections of cerulein in TRPV6mut/mut mice. RESULTS: We identified the variants c.629C>T (p.A210V) and c.970G>A (p.D324N) in TRPV6 in the index patient. Variants that affected function of the TRPV6 product were found in 13 of 300 patients (4.3%) and 1 of 1070 control individuals (0.1%) from Japan (odds ratio [OR], 48.4; 95% confidence interval [CI], 6.3-371.7; P = 2.4 × 10-8). Twelve of 124 patients (9.7%) with early-onset CP had such variants. In the replication set from Europe, 18 patients with CP (2.0%) carried variants that affected the function of the TRPV6 product compared with 0 control individuals (P = 6.2 × 10-8). Variants that did not affect the function of the TRPV6 product (p.I223T and p.D324N) were overrepresented in Japanese patients vs control individuals (OR, 10.9; 95% CI, 4.5-25.9; P = 7.4 × 10-9 for p.I223T and P = .01 for p.D324N), whereas the p.L299Q was overrepresented in European patients vs control individuals (OR, 3.0; 95% CI, 1.9-4.8; P = 1.2 × 10-5). TRPV6mut/mut mice given cerulein developed more severe pancreatitis than control mice, as shown by increased levels of pancreatic enzymes, histologic alterations, and pancreatic fibrosis. CONCLUSIONS: We found that patients with early-onset CP not associated with alcohol consumption carry variants in TRPV6 that affect the function of its product, perhaps by altering Ca2+ balance in pancreatic cells. TRPV6 regulates Ca2+ homeostasis and pancreatic inflammation.

Serum free light chain assessment in type 1 autoimmune pancreatitis.

BACKGROUND: /Object: Some patients with type 1 autoimmune pancreatitis (AIP), the pancreatic manifestation of IgG4-related disease, have normal serum IgG4. The aim of this study is to investigate the diagnostic value of measuring serum free light chains (FLCs) in type 1 AIP. MATERIALS AND METHODS: Thirty-seven patients with type 1 AIP, and 21 healthy, 17 alcoholic chronic pancreatitis (ACP), 21 idiopathic chronic pancreatitis (ICP) and 20 pancreatic cancer (PC) patients were enrolled. Serum IgG4 and FLC concentrations were measured using sFLC Freelite assays on a nephelometric analyzer. RESULTS: Active AIP patients have significantly higher serum levels of κ (median 30.97 (12.3-227.0) mg/L) and λFLC (median 20.53 (12.36-102.7) mg/L)) than healthy controls (κFLC; median 12.5 (3.1-52.1) mg/L), λFLC: median 12.45 (5.4-39.5) mg/L) (p < 0.05) correlating with raised serum IgG4, and significantly higher summated FLCs (∑) (median 53.09 (25.0-218.0) mg/L) than ICP patients (median 26.77 (15.0-89.2) mg/L) and healthy controls (median 24.43 (8.5-91.6) mg/L) (p < 0.05). AIP patients (median 1.43 (0.84-3.24)) showed significantly higher κ/λ ratios than ACP (median 0.83 (0.42-1.18)), ICP (median 0.87 (0.47-2.16)), PC patients (median 0.90 (0.48-1.27)) and healthy controls (median 0.963 (0.51-1.32)). There was a correlation between increased κ and λ FLCs levels and the number of affected organs involved in IgG4 related disease. CONCLUSION: Patients with type 1 AIP have increased serum k and λ FLC concentrations, Σ FLC, and κ/λ ratios. These novel biomarkers may be useful in the diagnosis of type 1 AIP and in monitoring disease activity.

Pancreatic cancer in patients with autoimmune pancreatitis: A scoping review.

BACKGROUND: Chronic pancreatitis is a known risk factor of pancreatic cancer (PDAC). A similar association has been suggested but not demonstrated for autoimmune pancreatitis (AIP). OBJECTIVE: The aim of our study was to identify and analyse all published cases of AIP and PDAC co-occurrence, focusing on the interval between the diagnoses and the cancer site within the pancreas. METHODS: Relevant studies were identified through automatic searches of the MEDLINE, EMBASE, Scopus, and Web of Science databases, and supplemented by manual checks of reference lists in all retrieved articles. Missing/unpublished data were obtained from the authors of relevant publications in the form of pre-prepared questionnaires. RESULTS: A total of 45 cases of PDAC in AIP patients were identified, of which 12 were excluded from the analysis due to suspicions of duplicity or lack of sufficient data. Thirty-one patients (94%) had type 1 AIP. Synchronous occurrence of PDAC and AIP was reported in 11 patients (33%), metachronous in 22 patients (67%). In the metachronous group, the median period between diagnoses was 66.5 months (2-186) and a majority of cancers (86%) occurred more than two years after AIP diagnosis. In most patients (70%), the cancer originated in the part of the pancreas affected by AIP. CONCLUSIONS: In the literature, there are reports on numerous cases of PDAC in AIP patients. PDAC is more frequent in AIP type 1 patients, typically metachronous in character, and generally found in the part of the pancreas affected by AIP.

Specific Smad2/3 Linker Phosphorylation Indicates Esophageal Non-neoplastic and Neoplastic Stem-Like Cells and Neoplastic Development.

BACKGROUND: There is little known about stem cells in human non-neoplastic and neoplastic esophageal epithelia. We have demonstrated expression of linker threonine-phosphorylated Smad2/3 (pSmad2/3L-Thr), suggesting presence of stem-like cells in mouse esophageal epithelium, and identified presence of pSmad2/3L-Thr-positive cells that might function as cancer stem cells in mouse model of colorectal carcinoma. AIMS: We explore whether pSmad2/3L-Thr can be used as a biomarker for stem cells of human esophageal epithelia and/or neoplasms. METHODS: We have used esophageal tissues from inpatients undergoing endoscopic submucosal dissection and performed double immunofluorescent staining of pSmad2/3L-Thr and Ki67, CDK4, p63, Sox2, CK14, p53, ALDH1, CD44 or D2-40 after which the sections were stained with hematoxylin and eosin. RESULTS: pSmad2/3L-Thr-positive cells showed immunohistochemical co-localization with CDK4, p63, CD44 and Sox2 in the basal and parabasal layers of non-neoplastic esophageal epithelia. In esophageal neoplasms, they showed immunohistochemical co-localization with p53, CDK4, ALDH1 and CD44. There was a significant increase in the percentage of pSmad2/3L-Thr-positive cells in the p53-positive neoplastic cell population with development of esophageal neoplasia. pSmad2/3L-Thr-positive cells localized to the lower section of low-grade intraepithelial neoplasia and were observed up to the upper section in carcinoma in situ. In invasive squamous cell carcinoma, they were scattered throughout the tumor with disappearance of polarity and were found in intraepithelial primary lesions and sites of submucosal and vessel invasion. CONCLUSIONS: We determined significant expression of pSmad2/3L-Thr in human esophageal non-neoplastic and neoplastic epithelia, indicating that these are epithelial stem-like cells and cancer stem cells, respectively, that correlate with developing esophageal neoplasms.

Recent advances of endoscopic retrograde cholangiopancreatography using balloon assisted endoscopy for pancreaticobiliary diseases in patients with surgically altered anatomy: Therapeutic strategy and management of difficult cases.

Endoscopic retrograde cholangiopancreatography (ERCP) is an endoscopic modality established for diagnosis and treatment of pancreaticobiliary diseases. However ERCP in patients with surgically altered anatomy (SAA) has been difficult, and more invasive therapies have been primarily selected. The development of balloon assisted endoscopes (BAEs) innovatively facilitated ERCP in such patients. Recent advances of BAEs and other devices greatly contributed to increasing success of ERCP using BAEs (BAE-ERCP). Furthermore, interventions using Endoscopic Ultrasound (EUS-intervention) have been reported to be useful for pancreaticobiliary diseases in patients with SAA, which provide more options for endoscopic therapies and are also expected as a rescue therapy for difficult cases of BAE-ERCP. In order to thoroughly complete endoscopic treatment for pancreaticobiliary diseases with SAA, it is important to standardize the BAE-ERCP procedures based on the features of respective endoscopes and to establish a strategy for endoscopic treatment which includes analysis of BAE-ERCP difficult cases and selection of cases for rescue therapy. In addition, it is essential to be acquainted with the characteristics of possible adverse events of the procedure and to be able to deal with them for safe accomplishment of endoscopic treatment.

Magnetic resonance cholangiopancreatography findings in early chronic pancreatitis diagnosed according to the Japanese Diagnostic Criteria.

OBJECTIVES: It is important for diagnosing early chronic pancreatitis (CP), which may be improved by therapeutic intervention. We aimed to examine the pancreatic ductal changes on magnetic resonance cholangiopancreatography (MRCP) in patients with early CP defined by the Japanese Diagnostic Criteria. METHODS: This retrospective study included patients suspected early CP and performed both endoscopic ultrasonography (EUS) and MRCP from January 2010 to August 2018. We assessed the diameter of the main pancreatic duct (MPD) and the number of irregularly dilated duct branches using MRCP imaging in early CP. RESULTS: We enrolled 165 patients and 25 patients (15%) fulfilled the diagnostic criteria for early CP. Irregular dilatation of ≥ 3 duct branches on MRCP was more often observed in early CP compared to non-early CP (P = 0.004), although MPD diameter was comparable (2.06 mm in early CP vs. 1.96 in non-early CP, P = 0.698). The sensitivity and specificity were 45% and 74%, respectively. The prevalence of positive MRCP findings in patients with ≥ 2 positive EUS findings was higher than that in patients with 1 positive EUS finding (P = 0.08) and in patients without an EUS finding (P < 0.001). There was no difference in the average diameter of MPD. CONCLUSION: Patients with early CP often exhibit alteration in duct branches and not in MPD in addition to parenchymal alteration. Both pancreatic parenchyma and duct branches might need to be evaluated by EUS and MRCP.

Extracellular vesicles microRNA analysis in type 1 autoimmune pancreatitis: Increased expression of microRNA-21.

BACKGROUND: The molecular basis of type 1 autoimmune pancreatitis (AIP) remains unclear. Recent attention on the role of extracellular vesicles microRNA (EV miRNA) in immune homeostasis has prompted us to perform an extensive miRNA screening of serum-derived EV in AIP. METHODS: EV miRNA expression was analyzed using microarrays in AIP, chronic pancreatitis (CP), and healthy adult (HC) samples (n = 10 from each group). Differences in signals, > 3 or <1/3 times, represented significant differences in expression. Another cohort of AIP (n = 14), CP (n = 10), and HC (n = 10) samples of EV miRNA was analyzed using reverse-transcription polymerase chain reaction (RT-PCR). miRNA expression in pancreatic tissues was evaluated using in situ hybridization (ISH) in three additional subjects from each group. RESULTS: Signals of eight miRNAs (miR-659-3p, -27a-3p, -99a-5p, -21-5p, -205-5p, -100-5p, -29c-3p, and -125b-1-3p) were significantly higher, while those of two miRNAs (miR-4252 and -5004-5p) were significantly lower in AIP than in HC. EV miR-21-5p was significantly up-regulated in AIP than in HC (P = 0.035) and CP (P = 0.048). The number of miR-21-5p positive inflammatory cells was significantly elevated in AIP than in CP (P = 0.014). CONCLUSIONS: Circulating EVs exhibited altered miRNA expression patterns with elevated miR-21-5p in AIP when compared with those in HC and CP. miR-21-5p was highly expressed in pancreatic inflammatory cells in AIP. Our data suggests that miR-21-5p may be involved in the regulation of effector pathways in the pathophysiology of AIP, thus differentiating AIP from CP.

Efficacy and limitations of the histological diagnosis of type 1 autoimmune pancreatitis with endoscopic ultrasound-guided fine needle biopsy with large tissue amounts.

OBJECTIVES: We examined the efficacy and limitations of acquiring large specimens by endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) for diagnosing type 1 autoimmune pancreatitis (AIP). METHODS: Patients from 12 institutions with non-neoplastic diseases or pancreatic ductal adenocarcinoma (PDAC) with large EUS-FNB specimens were investigated. Slides stained with hematoxylin-eosin, elastic, IgG4, and IgG stains were evaluated. The IgG4- and IgG-positive cell numbers were counted in three foci. The diagnoses were based on the Japan Pancreas Society 2011 (JPS 2011) criteria and the International Consensus Diagnostic Criteria (ICDC). RESULTS: We analyzed 85 non-neoplastic (definite type 1 AIP in 73/85 based on the ICDC) cases and 64 PDAC cases. IgG4-positive cells were numerous (>10 in 85.9%), and the IgG4/IgG ratios were high (>40% in 81.2%). Plasma cell crushing by an artifact caused unsuccessful immunostaining, notably in smaller samples. Tissue lengths were an important factor for the presence of storiform fibrosis and obliterative phlebitis, but storiform fibrosis was equivocal even in large tissues. A definite or possible histological diagnosis was achieved in 45.9% (39/85) and 41.2% (35/85), respectively, and contributed to the definite final diagnosis of type 1 AIP in 33.3% (ICDC) and 55.6% (JPS 2011) in cases with segmental/focal lesions. In the PDAC group, >10 IgG4-positive cells was rare (2/58), but elastic stains revealed fibrous venous occlusions in 10.3% (6/58). CONCLUSIONS: EUS-FNB with large tissue amounts was useful for diagnosing type 1 AIP, notably by facilitating successful IgG4 immunostaining, but definite diagnosis may not be achieved even in cases with large specimens.

Etiology and mortality in severe acute pancreatitis: A multicenter study in Japan.

BACKGROUND/OBJECTIVES: Severe acute pancreatitis (SAP) has a high mortality rate despite ongoing attempts to improve prognosis through a various therapeutic modalities. This study aimed to delineate etiology-based routes that may guide clinical decisions for the treatment of SAP. METHODS: Using data from a recent retrospective multicenter study in Japan, we analyzed the association between clinical outcomes, mainly in-hospital mortality and pancreatic infection, and various etiologies while considering confounding factors. We performed additional multivariate analyses and built decision tree models. RESULTS: The 1097 participating patients were classified into the following groups by etiology: alcohol (n = 436, 39.7%); cholelithiasis (n = 230, 21.0%); idiopathic (n = 227, 20.7%); and others (n = 204, 18.6%). Mortality at hospital discharge was 8.4%, 12.2%, 16.7%, and 16.2% in the alcohol, cholelithiasis, idiopathic, and others groups, respectively. According to multivariable analysis, early enteral nutrition (EN) was significantly associated with reduced in-hospital mortality only in the cholelithiasis group. However, there was a consistent association between age and the need for mechanical ventilation and increased mortality, regardless of etiology. Our decision tree models presented different contributing factors depending on the etiology and patient background. Interaction analysis showed that EN and the use of prophylactic antibiotics may influence these results differently according to etiology. CONCLUSIONS: No study has yet used comprehensive models to investigate etiology-related prognostic factors for SAP; our results can, therefore, be used as a reference for improving clinical decisions.