[Application of JSGPM classification in pancreaticobiliary maljunction].

Objective: To evaluate the clinical value of the Japanese Study Group on Pancreaticobiliary Maljunction(JSGPM) classification in the diagnosis and treatment of pancreaticobiliary maljunction (PBM). Methods: A retrospective cohort analysis was conducted on 103 patients diagnosed with PBM via endoscopic retrograde cholangiopancreatography at the Department of General Surgery, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine from January 2010 to September 2018. There were 32 male cases and 71 female cases; the age (M(IQR)) was 5.1 (39.0) years (range: 2.2 to 56.1 years), with 74 cases aged <12 years and 29 cases aged ≥12 years.The distribution characteristics, clinical manifestations, and treatment strategies of different JSGPM subtypes were compared between pediatric (<12 years) and adolescent/adult (≥12 years) patients. Normally distributed quantitative data were compared between two groups using the independent samples t-test, and among multiple groups using analysis of variance (ANOVA). Skewed quantitative data were compared using non-parametric tests. Categorical variables were compared using the χ² test or Fisher's exact test. Results: Among the 103 PBM patients, JSGPM classified 40 cases as type A (39.2%), 31 cases as type B (30.4%), 25 cases as type C (24.5%), and 6 as type D (5.9%), with no unclassifiable cases. Among patients aged ≥12 years, the incidence of type B PBM was higher than that in children <12 years (51.7% (15/29) vs. 21.6% (16/74); χ²=8.974, P<0.01), and type B was the predominant subtype without concurrent common bile duct dilation (≥12 years vs. <12 years: 12/15 vs. 7/16). Among the 7 pediatric cases (7/16) and 12 adult patients (12/15) with type B PBM without concurrent common bile duct dilation, none underwent extrahepatic bile duct resection; instead, they received only endoscopic sphincterotomy plus cholecystectomy. All patients were followed up for (36±26) months (range: 6 to 96 months), with no recurrence of biliary tract infections, obstructive jaundice, or pancreatitis. Conclusions: The JSGPM classification is concise, practical, and highly correlated with clinical features and prognostic risks, providing clear guidance for individualized diagnosis and treatment. This classification helps identify high-risk type B PBM patients and guides the implementation of precise preventive strategies, avoiding undertreatment or overtreatment.