Descriptive epidemiology and outcome of patients with intraductal papillary mucinous neoplasm (IPMN): a population-based comparison to pancreatic adenocarcinoma and review of literature.

Intraductal papillary neoplasm (IPMN) is an uncommon cancer of the pancreas, histologically characterized as a distinct entity by WHO in 1996, as noninvasive (adenoma, borderline neoplasm, carcinoma in situ) or invasive. Our understanding of this disease comes mainly from small retrospective reports and anecdotal experience. While it is clear that patients with benign IPMNs do better than patients with invasive IPMNs and adenocarcinoma, it is not clear if, once invasive, IPMNs have a more favorable prognosis than adenocarcinoma not associated with IPMNs. Our goal was to evaluate a large population-based cohort of patients with invasive IPMN and compare their demographic factors and outcomes to those of patients with pancreatic adenocarcinoma (PA). Using the Surveillance, Epidemiology, and End Results (SEER) database (1988 to 2003), we identified all patients with invasive IPMN or PA. A total of 2,166 patients with invasive IPMN and 35,515 with PA were identified. Patients with IPMN were younger than patients with PA at the time of diagnosis (67.0 vs. 70.1, P<.0001). The overall 5-year survival was 8.8% for IPMN (median, 5 months) and 3.7% for PA (median, 4 months, P < .0001). Patients with unresected IPMN had a 5-year survival rate of 4.2% compared to 2.2% in patients with unresected PA (P < .0001). Surgical resection was a significant independent predictor of improved survival, as was female gender, race other than white and black, married status and negative lymph nodes. We conclude, IPMN is a more indolent disease than PA. Patients with IPMN tend to present at a younger age, are more likely to have resectable disease, and are much more likely to undergo potentially curative resection. The long-term survival for patients with IPMN is significantly better when compared to the long-term survival of patients with PA.