Although pancreatic neuroendocrine neoplasms (PNENs) are relatively rare tumors, their number is increasing with advances in diagnostic imaging modalities. Even small lesions that are difficult to detect using computed tomography or magnetic resonance imaging can now be detected with endoscopic ultrasound (EUS). Contrast-enhanced EUS is useful, and not only diagnosis but also malignancy detection has become possible by evaluating the vascularity of tumors. Pathological diagnosis using EUS with fine-needle aspiration (EUS-FNA) is useful when diagnostic imaging is difficult. EUS-FNA can also be used to evaluate the grade of malignancy. Pooling the data of the studies that compared the PNENs grading between EUS-FNA samples and surgical specimens showed a concordance rate of 77.5% (κ-statistic = 0.65, 95% confidence interval = 0.59–0.71, p < 0.01). Stratified analysis for small tumor size (2 cm) showed that the concordance rate was 84.5% and the kappa correlation index was 0.59 (95% confidence interval = 0.43–0.74, p < 0.01). The evolution of ultrasound imaging technologies such as contrast-enhanced and elastography and the artificial intelligence that analyzes them, the evolution of needles, and genetic analysis, will further develop the diagnosis and treatment of PNENs in the future.

Objective Post–endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis involves persistent serum amylase levels of 3 times or more the standard upper limit. However, these criteria were mostly based on retrospective studies and not necessarily supported by diagnostic imaging. Our prospective study aimed to investigate cutoff serum amylase levels suggesting post-ERCP pancreatitis using computed tomography as the criterion standard. Methods We prospectively followed 2078 cases. Computed tomography was performed in patients whose serum amylase levels exceeded the institutional upper limit 12 to 24 hours after ERCP. Two expert radiologists blindly assessed the images and judged the presence or absence of pancreatitis. Correlations between serum amylase levels with pancreatitis were investigated using receiver operating characteristic analysis. Results Amylase levels increased in 416 (23.2%) of 1789 cases included, and 350 cases were analyzed using computed tomography. Post–endoscopic retrograde cholangiopancreatography pancreatitis was diagnosed in 12.0% (214/1789). The cutoff amylase levels for judging pancreatitis after 12 to 24 hours was 2.75 times higher than the institutional upper limit, with an area under the curve of 0.77. Conclusions The appropriate cutoff serum amylase level for judging post-ERCP pancreatitis at 12 to 24 hours after ERCP was 2.75 times higher than the institutional upper limit. These results may clarify the definition of post-ERCP pancreatitis.

Objectives Endoscopic ultrasonography is an important examination for periampullary diseases. The duodenum is filled with water to ensure a clear image and distend the duodenal wall without burying the papilla within duodenal folds; however, peristalsis frequently makes it difficult to maintain water within the duodenum. The gel immersion method (intestine is filled with viscosity gel) has recently been attracting attention. We evaluated the usefulness of using this method for endoscopic ultrasonography to detect and delineate the major duodenal papilla. Methods Fifty‐nine consecutive patients who underwent gel immersion‐endoscopic ultrasonography between February and March 2021 were included retrospectively. The papilla was observed by filling the duodenum with clear viscosity gel. Outcomes were the rate of duodenal distention, delineation rates of the papilla, the time required for delineation, volume of the gel used, and adverse events. Results Duodenal distention was excellent, good, and poor in 58%, 34%, and 7% of cases, respectively. The delineation rates of the papilla in the axial and longitudinal views were 98% and 66%, respectively. The median time required to delineate the papilla in each view was 3.1 (range, 1.0–1.4) and 7.9 (1.9–28.6) min; the median volume of the gel used was 80 (30–150) ml and 100 (50–200) ml, respectively. No adverse events were noted. Conclusions Gel immersion‐endoscopic ultrasonography provided sufficient duodenal distention, leading to high rates of detection and delineation of the papilla using a small volume of gel within a short time. This method may be useful for the evaluation of the ampullary region.

Objective The aim of this study was to identify the incidence of and risk factors for post–endoscopic retrograde cholangiopancreatography pancreatitis (PEP) after emergency endoscopic retrograde cholangiopancreatography (ERCP). Methods We performed a prospective multicenter observational study of 3914 patients who underwent ERCP. We compared the incidence of PEP after emergency and elective ERCP. Results A total of 3410 patients were enrolled in this study. Post-ERCP pancreatitis occurred in 44 of 800 patients (5.5%) and in 190 of 2418 patients (7.9%) in the emergency and elective groups, respectively. No significant difference was noted between the groups (odds ratio [OR], 0.73; 95% confidence interval [CI], 0.52–1.03; P = 0.07). Multivariate analysis showed that the following factors increased the risk for PEP after emergency ERCP: contrast medium injection into the pancreatic duct (OR, 2.56; 95% CI, 1.30–5.03; P = 0.005), >4 cannulation attempts (OR, 5.72; 95% CI, 2.61–12.50; P < 0.001), and endoscopic papillary balloon dilatation (OR, 9.24; 95% CI, 2.13–40.10; P < 0.001). Conclusions No significant difference was noted in the incidence of PEP in patients after emergency and elective ERCP. We may prevent PEP even after emergency ERCP by avoiding contrast injection into the pancreatic duct, multiple cannulation attempts, and endoscopic papillary balloon dilatation.

Background and Aim International consensus on the definition and classification of post‐endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) has been reached. However, the diagnosis and severity of PEP are often assessed according to the diagnostic criteria and classification for acute pancreatitis (AP). This study determined the incidence, severity, and risk factors of PEP diagnosed according to the diagnostic criteria and classification for AP in a large cohort. Methods This prospective, multicenter, observational cohort study conducted at five high‐volume centers included 1932 patients who underwent ERCP‐related procedures. The incidence, severity, and risk factors for PEP were evaluated. Results PEP occurred in 142 patients (7.3%); it was mild in 117 patients (6.0%) and severe in 25 patients (1.3%). According to the Cotton criteria, PEP occurred in 87 patients (4.5%); it was mild in 54 patients (2.8%), moderate in 20 patients (1.0%), and severe in 13 patients (0.7%). In the multivariate analysis, female sex (odds ratio [OR] 2.239; 95% confidence interval [CI] 1.546–3.243), naïve papilla (OR 3.047; 95% CI 1.803–5.150), surgically‐altered gastrointestinal anatomy (OR 2.538; 95% CI 1.342–4.802), procedure time after reaching the papilla (OR 1.009; 95% CI 1.001–1.017), pancreatic duct injection (OR 2.396; 95% CI 1.565–3.669), and intraductal ultrasonography (OR 1.641; 95% CI 1.024–2.629) were independent risk factors. Conclusion According to the diagnostic criteria and classification for AP, the incidence of PEP was higher than that according to the Cotton criteria and the severity of PEP tended to be severe.