Invasive intraductal papillary mucinous neoplasm: Predictors of survival and role of adjuvant therapy

Background: Adjuvant treatment for pancreatic adenocarcinoma has been shown to improve survival. An increasingly recognized 'subtype' of pancreatic adenocarcinoma is invasive intraductal papillary mucinous neoplasm (IPMN). It is unclear whether adjuvant treatment for invasive IPMN improves survival. This study aimed to determine the impact of adjuvant treatment in invasive IPMN. Methods: We conducted a retrospective analysis of merged clinical databases including 412 patients undergoing resection for IPMN at two academic institutions between 1989 and 2006. Results: Of 412 patients with IPMN who underwent pancreatectomy, 98 had invasive carcinoma. Median survival in invasive IPMN was 32 months. Adjuvant treatment did not affect median survival in node-positive or node-negative invasive IPMN. Biopsy-proven recurrence of invasive IPMN occurred in 45 patients (46%). The median disease-free interval from resection to recurrence was 27 months. Treatment of recurrences with chemotherapy or radiation therapy was not associated with a difference in survival; however, a subgroup of patients with recurrence in the remnant pancreas who underwent re-resection appeared to have more favourable outcomes. Conclusions: An invasive component measuring >2 cm and lymph node involvement are associated with poorer prognosis. Adjuvant therapy in invasive IPMN appears to confer no survival benefit. In selected patients with recurrence of invasive IPMN in the remnant pancreas, re-resection should be considered.