Simpson, Rachel E.Ceppa, Eugene P.Wu, Howard H.Akisik, FatihHouse, Michael G.Zyromski, Nicholas J.Nakeeb, AttilaAl-Haddad, Mohammad A.DeWitt, John M.Sherman, StuartSchmidt, C. Max2019-11-082019-11-082019-08Simpson, R. E., Ceppa, E. P., Wu, H. H., Akisik, F., House, M. G., Zyromski, N. J., … Schmidt, C. M. (2019). The Dilemma of the Dilated Main Pancreatic Duct in the Distal Pancreatic Remnant After Proximal Pancreatectomy for IPMN. Journal of Gastrointestinal Surgery, 23(8), 1593–1603. https://doi.org/10.1007/s11605-018-4026-0https://hdl.handle.net/1805/21301Objective(s) A dilated main pancreatic duct in the distal remnant after proximal pancreatectomy for intraductal papillary mucinous neoplasms (IPMN) poses a diagnostic dilemma. We sought to determine parameters predictive of remnant main-duct IPMN and malignancy during surveillance. Methods Three hundred seventeen patients underwent proximal pancreatectomy for IPMN (Indiana University, 1991–2016). Main-duct dilation included those ≥ 5 mm or “dilated” on radiographic reports. Statistics compared groups using Student’s T/Mann-Whitney U tests for continuous variables or chi-square/Fisher’s exact test for categorical variables with P < 0.05 considered significant. Results High-grade/invasive IPMN or adenocarcinoma at proximal pancreatectomy predicted malignant outcomes (100.0% malignant outcomes; P < 0.001) in remnant surveillance. Low/moderate-grade lesions revealed benign outcomes at last surveillance regardless of duct diameter. Twenty of 21 patients undergoing distal remnant reoperation had a dilated main duct. Seven had main-duct IPMN on remnant pathology; these patients had greater mean maximum main-duct diameter prior to reoperation (9.5 vs 6.2 mm, P = 0.072), but this did not reach statistical significance. Several features showed high sensitivity/specificity for remnant main-duct IPMN. Conclusions Remnant main-duct dilation after proximal pancreatectomy for IPMN remains a diagnostic dilemma. Several parameters show a promise in accurately diagnosing main-duct IPMN in the remnant.enIUPUI Open Access Policypancreatic ductpancreatic neoplasmsmucinous neoplasmsArticle