Outcomes of Primary Surveillance for Intraductal Papillary Mucinous Neoplasm

Abstract

Limited data are available regarding the natural history of patients undergoing primary surveillance for intraductal papillary mucinous neoplasm (IPMN). We hypothesize that symptoms, radiologic characteristics, and cytopathology will predict cancer risk during surveillance. Between March 2002 and March 2010, 522 patients were diagnosed with IPMN at a single, high-volume institution. Low versus high oncologic risk was stratified prospectively. Patients with under 3 months of surveillance were excluded. Two hundred ninety-two patients underwent primary surveillance for IPMN. Two hundred forty-four (84%) were classified as low-risk IPMN. Mean surveillance duration was 35 (4–99) months. Thirty (12%) patients initially stratified as low-risk developed a new indication for pancreatic resection. Only 28 underwent resection, and pathologic tissue analysis revealed 27 (96%) low-grade IPMN and one (4%) high-grade dysplastic IPMN. Overall, two (1%) patients initially determined to be low-risk developed invasive cancer. Forty-eight (16%) patients stratified as high-risk IPMN were initially managed nonoperatively. Of the 13 (27%) high-risk patients that died during follow-up, two (15%) died from pancreatic cancer. Progression to pancreatic cancer during surveillance for low-risk IPMN was rare. Current indications for resection did not forecast malignancy. Poor operative candidates with high-risk IPMN progressed to invasive cancer more commonly, though a substantial portion succumbed to non-IPMN-related death.