Outcomes following resection of invasive and noninvasive intraductal papillary mucinous neoplasms of the pancreas

Background Since any intraductal papillary mucinous neoplasm (IPMN) is at least premalignant, avoiding conversion to invasion by pancreatic resection should provide a survival advantage—but how much? Methods We reviewed 100 cases of IPMN that were resected. Survival was compared between 3 groups: noninvasive IPMN (n = 75), invasive IPMN (n = 25), and invasive ductal adenocarcinoma (n = 24), the latter matched by tumor-node-metastasis (TNM) stage to the IPMN invasive group. Results The 5-year disease-specific survival was significantly better for the noninvasive IPMN group (100%) than the invasive IPMN group (46%). Tumor recurrence was infrequent with noninvasive IPMNs (1.3% benign IPMN). Recurrence was common in the invasive IPMN group (46%). Even the subgroup with stage 1 disease had a 25% recurrence of malignancy. Survival curves were not different (P = .11) between the cases matched by stage for those with invasive IPMN cases versus cases with ductal adenocarcinoma. Conclusion Patients with the invasive form of IPMN will have a similarly poor survival as those with ductal adenocarcinoma. In patients thought to have a benign IPMN, these lesions should be removed to avoid conversion to invasive cancer and to preserve the opportunity for the more favorable prognosis observed in this study.