Pancreatic ductal adenocarcinomas concomitant with intraductal papillary mucinous neoplasms of the pancreas: A investigation of those clinicopathological features by analyzing 48 patients who underwent surgery for those lesions.

BACKGROUND: Differences between pancreatic ductal adenocarcinomas (PDACs) concomitant with intraductal papillary mucinous neoplasm (IPMN) (C-PDACs), those without IPMN (NC-PDACs) and invasive cancers derived from IPMN (IC-Ds) have not been fully clarified. METHODS: Forty-eight patients with C-PDAC were included to investigate the differences in 1) clinicopathological features and 2) post-operative courses among the three invasive cancer groups. RESULTS: 1) Characteristics of C-PDACs were mostly similar to those of NC-PDACs; whereas, between C-PDACs and IC-Ds, the rate of mucinous carcinoma (2%/25%, p = 0.003) and pathological stage (IA, 15%/36%, p = 0.033; III, 31%/4%, p = 0.015) significantly differed. Most C-PDACs coexisted with small, multifocal IPMNs without mural nodules. 2) Cumulative 5-year recurrence-free survival (RFS) rate related to extra-pancreatic recurrence was significantly worse in C-PDACs than in IC-Ds (35%/69%, p = 0.008) and was not significantly different between C-PDACs and NC-PDACs (35%/18%). This related to intra-pancreatic recurrence tended to be poor in the order of IC-Ds, C-PDACs, and NC-PDACs (69%/82%/93%). CONCLUSIONS: Because characteristics of IPMNs remarkably differed between C-PDACs and IC-Ds, another algorithm specific to the early detection of C-PDACs is necessary. Appropriate post-operative managements according to the two types of recurrences may contribute to the improvement in the prognoses of C-PDACs/IC-Ds.

Pancreatic duct lavage cytology combined with a cell-block method for patients with possible pancreatic ductal adenocarcinomas, including pancreatic carcinoma in situ.

BACKGROUND/AIMS: This study aimed to clarify the efficacy and safety of pancreatic duct lavage cytology combined with a cell-block method (PLC-CB) for possible pancreatic ductal adenocarcinomas (PDACs). METHODS: This study included 41 patients with suspected PDACs who underwent PLC-CB mainly because they were unfit for undergoing endoscopic ultrasonography-guided fine needle aspiration. A 6-Fr double lumen catheter was mainly used to perform PLC-CB. Final diagnoses were obtained from the findings of resected specimens or clinical outcomes during surveillance after PLC-CB. RESULTS: Histocytological evaluations using PLC-CB were performed in 87.8% (36/41) of the patients. For 31 of the 36 patients, final diagnoses (invasive PDAC, 12; pancreatic carcinoma in situ, 5; benignancy, 14) were made, and the remaining five patients were excluded due to lack of surveillance periods after PLC-CB. For 31 patients, the sensitivity, specificity, and accuracy of PLC-CB for detecting malignancy were 94.1%, 100%, and 96.8%, respectively. In addition, they were 87.5%, 100%, and 94.1%, respectively, in 17 patients without pancreatic masses detectable using endoscopic ultrasonography. Four patients developed postprocedural pancreatitis, which improved with conservative therapy. CONCLUSION: PLC-CB has an excellent ability to detect malignancies in patients with possible PDACs, including pancreatic carcinoma in situ.

Diagnostic value of homogenous delayed enhancement in contrast-enhanced computed tomography images and endoscopic ultrasound-guided tissue acquisition for patients with focal autoimmune pancreatitis.

BACKGROUND/AIMS: We aimed to investigate (1) promising clinical findings for the recognition of focal type autoimmune pancreatitis (FAIP) and (2) the impact of endoscopic ultrasound (EUS)-guided tissue acquisition (EUS-TA) on the diagnosis of FAIP. METHODS: Twenty-three patients with FAIP were involved in this study, and 44 patients with resected pancreatic ductal adenocarcinoma (PDAC) were included in the control group. RESULTS: (1) Multivariate analysis revealed that homogeneous delayed enhancement on contrast-enhanced computed tomography was a significant factor indicative of FAIP compared to PDAC (90% vs. 7%, p=0.015). (2) For 13 of 17 FAIP patients (76.5%) who underwent EUS-TA, EUS-TA aided the diagnostic confirmation of AIPs, and only one patient (5.9%) was found to have AIP after surgery. On the other hand, of the six patients who did not undergo EUS-TA, three (50.0%) underwent surgery for pancreatic lesions. CONCLUSION: Homogeneous delayed enhancement on contrast-enhanced computed tomography was the most useful clinical factor for discriminating FAIPs from PDACs. EUS-TA is mandatory for diagnostic confirmation of FAIP lesions and can contribute to a reduction in the rate of unnecessary surgery for patients with FAIP.

Mixed neuroendocrine-non-neuroendocrine neoplasm with mucinous adenocarcinoma and amphicrine carcinoma components in the bile duct: an autopsy case.

We report the first case of bile duct mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN) that had a mucinous carcinoma component. An 88-year-old man with biliary obstruction was diagnosed as having distal bile duct cancer using imaging examinations and endoscopic biopsy. The patient received the best supportive care without surgical resection for 13 months until death. An autopsy revealed a bulky mass involving the distal bile duct and multiple metastases in intra-abdominal lymph nodes, the liver, and the lungs. The primary cancer was microscopically diagnosed as a MiNEN, which consisted of mucinous adenocarcinoma and large cell-type neuroendocrine carcinoma (NEC) components. Metastatic lesions in the liver and lungs were composed of only NEC with rich extracellular mucin without adenocarcinoma cells. Using electron microscopy and immunohistochemistry, it was proved that all NEC cells in both primary and metastatic lesions had amphicrine features. On the basis of pathological findings, we thought that the MiNEN was initially derived from a mucinous adenocarcinoma that dedifferentiated to amphicrine NEC cells with mucin production.

[Endoscopic mucosal resection of localized plasmablastic lymphoma with early rectal cancer:a rare case report and literature review].

A 79-year-old male with a positive fecal occult blood test result underwent total colonoscopy, which revealed a 15-mm-semipedunculated polyp in the rectum. The polyp appeared to be an adenoma using narrow-band imaging observation in magnifying endoscopy, although a 3mm reddish segment with a different surface structure was identified adjacent to the base of the polyp. En-bloc endoscopic mucosal resection (EMR) was performed. From the pathological evaluation using the specimen, the polyp was mainly a tubular adenoma with an adenocarcinoma component within the lesion. Additionally, a tiny plasmablastic lymphoma (PBL) component, which was positive for CD45, CD79a, CD30, CD38, MUM1, and lambda light chain;negative for CD3, CD5, CD20, CD56, CD138, cyclin D1, PAX5, IgG, IgA, IgM, IgE, HHV8, and kappa light chain, coexisted near the stalk. The proliferation index using Ki-67 immunohistochemistry was approximately 80%. Furthermore, Epstein-Barr virus-encoded RNAs were identified in in-situ hybridization, although the human immunodeficiency virus was not detected. The patient received contrast-enhanced computed tomography (CT) and positron emission tomography-CT (PET-CT) follow-ups after treatment without recurrence for two years. This is the first report of gastrointestinal PBL that could be treated using EMR.

Early and long-term clinical outcomes of endoscopic interventions for benign pancreatic duct stricture/obstruction-the possibility of additional clinical effects of endoscopic ultrasonography-guided pancreatic drainage.

OBJECTIVES: For benign pancreatic duct strictures/obstructions (BPDS/O), endoscopic ultrasonography-guided pancreatic drainage (EUS-PD) is performed when endoscopic transpapillary pancreatic drainage (ETPD) fails. We clarified the clinical outcomes for patients with BPDS/O who underwent endoscopic interventions through the era where EUS-PD was available. METHODS: Forty-five patients with BPDS/O who underwent ETPD/EUS-PD were included. We retrospectively investigated overall technical and clinical success rates for endoscopic interventions, adverse events, and clinical outcomes after successful endoscopic interventions. RESULTS: The technical success rates for ETPD and EUS-PD were 77% (35/45) and 80% (8/10), respectively, and the overall technical success rate using two drainage procedures was 91% (41/45). Among the 41 patients who underwent successful endoscopic procedures, the clinical success rates were 97% for the symptomatic patients (35/36). The rates of procedure-related pancreatitis after ETPD and EUS-PD were 13% and 30%, respectively. After successful endoscopic interventions, the cumulative 3-year rate of developing recurrent symptoms/pancreatitis was calculated to be 27%, and only two patients finally needed surgery. Continuous smoking after endoscopic interventions was shown to be a risk factor for developing recurrent symptoms/pancreatitis. CONCLUSIONS: By adding EUS-PD to ETPD, the technical success rate for endoscopic interventions for BPDS/O was more than 90%, and the clinical success rate was nearly 100%. Due to the low rate of surgery after endoscopic interventions, including EUS-PD, for patients with BPDS/O, EUS-PD may contribute to their good clinical courses as a salvage treatment for refractory BPDS/O.

Endoscopic Ultrasonography-guided Fine-needle Aspiration Cytology Combined with a Cell-block Method for Gastrointestinal Subepithelial Lesions.

Objective The diagnostic accuracy of an endoscopic ultrasound-guided fine-needle aspiration cytology/biopsy combined with a cell-block method (FNA-CB) for gastrointestinal subepithelial lesions (GI-SELs) has not been fully studied. Methods A total of 109 patients (with 110 GI-SELs) were evaluated to clarify the rate of obtaining evaluable histology specimens using FNA-CB. In addition, we investigated the following: 1) the accuracy for determining the histology, 2) effects of the number of cell clusters obtained via FNA-CB, 3) correlation of the Ki67 labelling index (Ki67LI) of the gastrointestinal stromal tumor (GIST) lesions between FNA-CB and resected specimens, and 4) clinical courses for patients followed up after FNA-CB. Results Of the 110 GI-SELs for which FNA-CB was performed, 95 (86%) were able to be histologically evaluated using the first FNA-CB. For the 70 resected GI-SELs, the accuracy of FNA-CB to determine histology was 96%, remaining at 90% even when only a few cell clusters were obtained. The concordance rate of the risk-grouping of GIST (high-risk, Ki67LI ≥8; low-risk, <8) between FNA-CB and resected specimens was 84%. Of the 29 patients followed up after the first FNA-CB, 12 with benign GI-SELs determined using the first FNA-CB showed no obvious increases in their GI-SEL sizes. Conclusion Since FNA-CB can be used to determine the histology and reproductive activity of GI-SELs accurately, not only preoperative histological confirmation but also reliable information to determine clinical plans, such as follow-up without surgery or neoadjuvant chemotherapy, can be obtained.

Pancreatic Ductal Adenocarcinoma Concomitant with Main Duct Type Intraductal Papillary Mucinous Neoplasm of the Pancreas: A Case Report.

BACKGROUND Intraductal papillary mucinous neoplasm of the pancreas (IPMN) and pancreatic ductal adenocarcinoma (PDAC) often coexist in the same pancreas. Almost all IPMNs involving PDACs concomitant with IPMN have been shown to be branch duct type IPMNs (BD-IPMNs), and their histological subtypes are gastric type. Therefore, PDACs concomitant with main duct type IPMNs (MD-IPMNs) are considered to be rare. We herein report a rare case preoperatively diagnosed as being a PDAC concomitant with MD-IPMN on the basis of imaging findings and histological findings of pancreatic specimens endoscopically obtained from 2 lesions. CASE REPORT A 67-year-old man was referred to our hospital due to an enlarged pancreas. Using imaging studies, a solid mass was found in the pancreatic head and intraductal papillary masses in the dilated main pancreatic duct of the body and tail with a fistula in the duodenum. On the basis of histological results using specimens endoscopically obtained from each of the 2 lesions, total pancreatectomy was planned due to suspected PDAC concomitant with an MD-IPMN. Finally, resected specimens were used to confirm the presence of a rare case of PDAC concomitant with MD-IPMN. CONCLUSIONS We encountered a rare case of a PDAC concomitant with an MD-IPMN which could be preoperatively diagnosed by using imaging studies and histological specimens endoscopically obtained. In addition to invasive cancers derived from IPMNs, PDACs concomitant with IPMNs can rarely develop in the pancreas involving MD-IPMNs.

Endoscopic Interventions for the Early and Remission Phases of Acute Biliary Pancreatitis: What are the More Concrete and Practical Situations for Performing Them?

BACKGROUND/AIMS: The use of endoscopic intervention (EI) for acute biliary pancreatitis (ABP) remains controversial because the severity of biliary obstruction/cholangitis/pancreatitis is not reflected in the indications for early EI (EEI). METHODS: A total of 148 patients with ABP were included to investigate 1) the differences in the rate of worsening cholangitis/pancreatitis between the EEI group and the early conservative management (ECM) group, especially for each severity of cholangitis/pancreatitis, and 2) the diagnostic ability of imaging studies, including endoscopic ultrasound (EUS), to detect common bile duct stones (CBDSs) in the ECM group. RESULTS: No differences were observed in the rate of worsening cholangitis between the EEI and ECM groups, regardless of the severity of cholangitis and/or the existence of impacted CBDSs. Among patients without impacted CBDSs and moderate/severe cholangitis, worsening pancreatitis was significantly more frequent in the EEI group (18% vs. 4%, p=0.048). In patients in the ECM group, the sensitivity and specificity for detecting CBDSs were 73% and 98%, respectively, for EUS, whereas the values were 13% and 92%, respectively, for magnetic resonance cholangiopancreatography. CONCLUSION: EEI should be avoided in the absence of moderate/severe cholangitis and/or impacted CBDSs because of the high rate of worsening pancreatitis. EUS can contribute to the accurate detection of residual CBDSs, for the determination of the need for elective EI.

Cholangioscopy- versus fluoroscopy-guided transpapillary mapping biopsy for preoperative evaluation of extrahepatic cholangiocarcinoma: a prospective randomized crossover study.

BACKGROUND: To evaluate the lateral extent of extrahepatic cholangiocarcinoma, the value of cholangioscopy-guided mapping biopsy (CMB) compared with that of fluoroscopy-guided mapping biopsy (FMB) remains unknown. The aim of this study was to compare these two techniques. METHODS: In this prospective, randomized, crossover study, both CMB and FMB techniques were performed for all patients in a randomized order. Target sites for the mapping biopsy were determined based on resection lines of possible surgical procedures. At least two biopsy strokes were attempted at each target site. The primary outcome was the rate of site-based successful biopsies, which was defined as acquisition of epithelium-containing material appropriate for diagnosing benignancy/malignancy from each site, regardless of amount of materials obtained from the same site. RESULTS: Between September 2016 and October 2018, 28 patients (16 distal bile duct cancer and 12 perihilar bile duct cancer) were enrolled and divided into two groups of 14 patients: CMB first and FMB first. Although all 118 target sites could be approached using CMB, FMB forceps reached only 71% of them with significantly poor accessibility to the B2/3 confluence. Since several materials were too small and did not contain epithelium, the overall rates of site-based successful biopsies were 78% (92/118) using CMB and 64% (76/118) using FMB (P = 0.031). CONCLUSIONS: The rate of site-based successful biopsies using CMB was significantly higher than that using FMB when evaluated using specimens obtained from several biopsy strokes.

Value of repeated cytology for intraductal papillary mucinous neoplasms of the pancreas with high risk potential of malignancy: Is it a promising method for monitoring a malignant transformation?

OBJECTIVES: The efficacy of and indications for cytological reexamination to detect malignant changes in branch duct type intraductal papillary mucinous neoplasms (BD-IPMNs) have not been studied in detail. We conducted a retrospective study to evaluate the efficacy and indications of cytological reexamination by using pancreatic juice (repeated cytology) for BD-IPMNs. METHODS: Forty-five patients who underwent repeated cytology after a diagnosis of benignancy by using initial cytology were recruited for this study. RESULTS: Thirty-eight patients, excluding 7 patients with lack of surveillance period after the final cytology, were classified into Malignancy (n = 13) and Benignancy groups (n = 25) on the bases of the findings from resected specimens or changes in BD-IPMNs after repeated cytology. The sensitivity and specificity to detect malignant changes in BD-IPMNs by using repeated cytology were 62% and 100%, respectively. For the 12 patients with mural nodules (MNs) ≥ 5 mm (67% of them were malignant), the sensitivity was 50%, whereas, for the 26 patients without MNs ≥ 5 mm (19% of them were malignant), it was 80%. In addition, malignant changes in BD-IPMNs after initial cytology occurred in 62% of the patients with changes in the MNs and 27% of the patients with an increase in the cyst size. CONCLUSION: Repeated cytology can play a role in the determination for surgery even after a diagnosis of benignancy by using initial cytology, especially for BD-IPMNs without MNs ≥5 mm. In addition, changes in the MNs or cyst size may be appropriate indications for repeated cytology.

[Helicobacter pylori-negative gastric mucosa-associated lymphoid tissue (MALT) lymphoma with MALT translocation gene 1 diagnosed using an endoscopic submucosal dissection specimen].

A 15-mm whitish, depressed lesion was observed in the stomach of a 39-year-old using screening esophagogastroduodenoscopy. The lesion had grown to a size of 40mm and had a cobblestone-like appearance at an 11-year endoscopic follow-up. Using endoscopic submucosal dissection (ESD) as a diagnostic therapy, gastric mucosa-associated lymphoid tissue (MALT) lymphoma with MALT translocation gene 1 without Helicobacter pylori infection was detected. Although the patient did not undergo additional treatments, he remained alive without for recurrence 5 years after ESD.

Peroral Cholangioscopy-guided Electrohydraulic Lithotripsy with a SpyGlass DS Versus a Conventional Digital Cholangioscope for Difficult Bile Duct Stones.

Objective Recently, a new digital peroral cholangioscopy (POCS) system, the SpyGlass DS (SpyDS), has been used for POCS-guided lithotripsy for difficult bile duct stones (DBDSs). The aim of this retrospective study was to compare the efficacy of SpyDS-guided electrohydraulic lithotripsy (EHL) for DBDS with that of a conventional digital cholangioscope. Methods Seventeen consecutive patients who had undergone POCS-guided EHL for DBDS with the SpyDS between October 2015 and January 2019 were enrolled in this study group (SpyDS group) using a prospectively maintained database. Fifteen other consecutive patients who had undergone POCS-guided EHL with a conventional digital cholangioscope (CHF-B260) just prior to the introduction of the SpyDS between December 2006 and September 2015 were analyzed as a control group (CHF group). The main outcome measurement was the total procedure time to complete stone removal. Results The rate of complete stone removal was 100% for both groups. The mean total procedure time for the SpyDS group was significantly shorter than that for the CHF group (67±30 minutes vs. 107±64 minutes, p=0.038). The mean number of endoscopic sessions for the SpyDS group was significantly lower than that for the CHF group (1.35±0.49 vs. 2.00±0.85, p=0.037). There were no significant differences in the rate of adverse events between the two groups. Conclusion The SpyDS appears useful for decreasing the procedure time and number of endoscopic sessions for complete stone removal in POCS-guided EHL for DBDS compared with a conventional digital cholangioscope.

Inside Plastic Stents versus Metal Stents for Treating Unresectable Malignant Perihilar Biliary Obstructions: A Retrospective Comparative Study.

BACKGROUND/AIMS: The aim of this study was to evaluate outcomes of inside plastic stents (iPSs) versus those of metal stents (MSs) for treating unresectable perihilar malignant obstructions. METHODS: For all patients who underwent endoscopic suprapapillary placement of iPS(s) or MS(s) as the first permanent biliary drainage for unresectable malignant perihilar obstructions between January 2014 and August 2019, clinical outcomes using iPSs (n=20) and MSs (n=85), including clinical efficacy, adverse events, and time to recurrence of biliary obstruction (RBO), were retrospectively evaluated. RESULTS: There were no differences in clinical effectiveness (95% for the iPS group vs. 92% for the MS group, p=1.00). Procedure-related adverse events, including pancreatitis, acute cholangitis, acute cholecystitis, and death, were observed for 8% of the MS group, although no patient in the iPS group developed such adverse events. The median time to RBO was 561 days (95% confidence interval, 0-1,186 days) for iPSs and 209 days (127-291 days) for MSs, showing a significant difference (p=0.008). CONCLUSION: Time to RBO after iPS placement was significantly longer than that after MS placement. IPSs, which are removable, unlike MSs, were an acceptable option.

Value of pancreatic and biliary flow MR imaging in the evaluation of pancreaticobiliary disorders.

Researchers have examined the possibility of studying pancreatic and biliary flow and using to aid the pathological evaluation of pancreaticobiliary diseases. Recently, a new method using MR imaging (MRI) has been developed for the direct visualization of pancreatic juice flow, based on a spin labeling technique. This technique enables direct visualization of pancreatic or bile duct juice flow and has various clinical applications relating to pancreaticobiliary disease. This review discusses the principle of pancreatic and biliary flow MRI with spin labeling and typical application examples such as the evaluation of the exocrine function of the pancreas in cases of chronic pancreatitis and the visualization of pancreatic juice reflux into the bile duct. Moreover other application is also discussed.

[Synchronous double primary cancers of a mixed adenoneuroendocrine carcinoma of the distal bile duct and a carcinoma in situ in the perihilar bile duct].

We report the rare case of a 69-year-old man who underwent resection of a mixed adenoneuroendocrine carcinoma (MANEC) of the distal bile duct and a carcinoma in situ in the perihilar bile duct. The patient was admitted to our hospital for obstructive jaundice. Imaging studies revealed a mass in the distal bile duct, and an abnormal epithelium was detected in the perihilar bile duct using peroral cholangioscopy. Bile cytology and transpapillary biopsy of the tumor revealed adenocarcinoma. We diagnosed this patient with distal cholangiocarcinoma with extensive intraepithelial progression toward the perihilar bile duct and performed a subtotal stomach-preserving pancreaticoduodenectomy and left hepatectomy. According to the histological examination of the resected specimens, we found a MANEC in the distal bile duct and a carcinoma in situ in the perihilar bile duct. Together, they were diagnosed as synchronous double primary cancers due to the lack of pathological transition between them.

Long-term Outcomes of Endoscopic Papillary Large-balloon Dilation for Common Bile Duct Stones.

Objective Endoscopic papillary large-balloon dilation (EPLBD) for common bile duct (CBD) stone removal has been confirmed to be safe and effective in the short term. The long-term outcomes of EPLBD, which have not been sufficiently evaluated, were therefore investigated in this study. Methods For patients who had undergone endoscopic CBD stone removal with EPLBD between October 2011 and December 2015, follow-up surveys were conducted using a postal survey, telephone interview, or medical record review in August 2017. The main outcome measurement was the recurrence rate of CBD stones after complete stone removal with EPLBD in patients who received follow-up for more than one year. Risk factors for such recurrence were secondarily analyzed. Results Of the 98 patients treated using EPLBD, 93 (95%) were followed up after complete stone removal and analyzed for the long-term outcomes. During the mean follow-up period of 33.7±16.6 months, CBD stones recurred in 16 patients (17%) with a mean interval of 12.7±12.7 months. Univariate analyses showed that a large stone size, multiple stones, a large distal CBD diameter, and a history of cholecystectomy were significant risk factors for stone recurrence (p=0.022, 0.013, 0.001 and 0.035, respectively). The large distal CBD diameter was the only significant risk factor for stone recurrence in a multivariate analysis (hazard ratio, 1.227; p=0.031). Conclusion The long-term outcomes of EPLBD for CBD stones, including the rate of stone recurrence, were found to be acceptable. A large distal CBD diameter was an independent risk factor for stone recurrence.

Predictive Value of Localized Stenosis of the Main Pancreatic Duct for Early Detection of Pancreatic Cancer.

BACKGROUND/AIMS: In this study, we aimed to evaluate the predictive value of localized stenosis of the main pancreatic duct (MPD) for early detection of pancreatic cancer. METHODS: Among 689 patients who underwent endoscopic retrograde pancreatography from January 2008 to September 2018, 19 patients with MPD findings were enrolled. These patients showed findings for indicating suspicious pancreatic cancer at an early stage (FiCE); FiCE was defined as a single, localized stenosis in the MPD without a detectable mass (using any other imaging methods) and without other pancreatic diseases, such as definite chronic pancreatitis, intraductal papillary mucinous neoplasm, and autoimmune pancreatitis. Final diagnoses were established by examining resected specimens or through follow-up examinations after an interval of >5 years. RESULTS: Among 19 patients with FiCE, 11 underwent surgical resection and 8 were evaluated after a >5-year observation period. The final diagnosis of the MPD stenosis was judged to be pancreatic cancer in 9 patients (47%), including 3 with intraepithelial cancer, and to be a non-neoplastic change in 10. The sensitivity, specificity, and accuracy of preoperative pancreatic juice cytology were 75%, 100%, and 88%, respectively. CONCLUSION: The predictive value of FiCE for pancreatic cancer prevalence was 47%. Histological confirmation with pancreatic juice cytology is necessary before surgical resection.

Endoscopic Ultrasonography-Guided Gallbladder Drainage as a Treatment Option for Acute Cholecystitis after Metal Stent Placement in Malignant Biliary Strictures.

BACKGROUND/AIMS: It is often difficult to manage acute cholecystitis after metal stent (MS) placement in unresectable malignant biliary strictures. The aim of this study was to evaluate the feasibility of endoscopic ultrasonography-guided gallbladder drainage (EUS-GBD) for acute cholecystitis. METHODS: The clinical outcomes of 10 patients who underwent EUS-GBD for acute cholecystitis after MS placement between January 2011 and August 2018 were retrospectively evaluated. The procedural outcomes of percutaneous transhepatic gallbladder drainage (PTGBD) with tube placement (n=11 cases) and aspiration (PTGBA) (n=27 cases) during the study period were evaluated as a reference. RESULTS: The technical success and clinical effectiveness rates of EUS-GBD were 90% (9/10) and 89% (8/9), respectively. Severe bile leakage that required surgical treatment occurred in one case. Acute cholecystitis recurred after stent dislocation in 38% (3/8) of the cases. Both PTGBD and PTGBA were technically successful in all cases without severe adverse events and clinically effective in 91% and 63% of the cases, respectively. CONCLUSION: EUS-GBD after MS placement was a feasible option for treating acute cholecystitis. However, it was a rescue technique following the established percutaneous intervention in the current setting because of the immature technical methodology, including dedicated devices, which need further development.

Should we regard all main duct type intraductal papillary mucinous neoplasms of the pancreas (MD-IPMN) as an indication of surgery? -A retrospective study in 29 patients with MD-IPMN showing mural nodules.

PURPOSE: To elucidate predictive factors for malignant main duct type IPMN (MD-IPMN). METHODS: All 29 subjects had mural nodules (MNs) in the main pancreatic duct (MPD) on preoperative endoscopic ultrasonography and underwent surgery (19, malignant; 10, benign). Possible predictive factors for malignancy such as background, imaging, and histological factors including histological subtype (HS), were evaluated. RESULTS: Multivariate analysis revealed an MPD diameter of ≥12 mm (p = 0.042) and non-gastric type (p = 0.001) to be the statistically significant predictive factors for malignancy. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy to detect malignancy by using "an MPD diameter of ≥12 mm and/or non-gastric type" were 95%, 70%, 86%, 88%, and 86%, respectively. In 7 subjects in whom HS was preoperatively evaluated using pancreatic specimens obtained before surgery, the agreement rate of the preoperative HS with definitive HS evaluated using resected specimens was 86%. CONCLUSIONS: For MD-IPMNs with MNs, "an MPD diameter of ≥12 mm and/or non-gastric type" are indicated for surgery. On the other hand, careful surveillance without immediate pancreatic surgery may be an option for MD-IPMNs showing both an MPD diameter of <12 mm and gastric type.