Patterns of Recurrence After Resection of IPMN

OBJECTIVE: To describe the patterns of recurrence after resection of intraductal papillary mucinous neoplasms (IPMN) of the pancreas. BACKGROUND: IPMNs represent an increasing indication for pancreatic resection, but little is known about the actual incidence and the patterns of recurrence after surgical excision. METHODS: Retrospective review of 412 resected IPMNs from 1990 to 2013 who have had near-complete follow-up. RESULTS: Median age of the cohort was 68 years, 56% had branch duct (BD)-IPMN and 21% had invasive cancers. Nineteen patients (5%) had distinct pancreatic ductal adenocarcinoma (PDAC) and were excluded from the recurrence analysis. After a median of 58 months, 65 of 381 patients (17%) experienced recurrence of the IPMN, and 5- and 10-year disease-free survival (DFS) was 82% and 78%, respectively. Only 2 patients (0.5%) developed metachronous PDAC. In 33 patients (9%), a residual BD-IPMN was left in the pancreatic remnant, but none of these significantly grew or required reoperation. Invasive component and resection margin positive for IPMN were predictors of recurrence (P < 0.05). Invasive IPMN recurred in 45% of cases, whereas noninvasive in only 9% and later (P < 0.001), but patterns depended on IPMN subtypes. Only 9 patients required reoperation for recurrence, with good long-term outcome particularly for oncocytic IPMNs. CONCLUSIONS: Recurrence of noninvasive BD-IPMN is infrequent and surveillance may be avoided in selected cases. In invasive IPMN recurrence depends on N status, pancreatic margin, and invasive type.