Trends in malignant intraductal papillary mucinous neoplasm in US adults from 1990 to 2010: A SEER database analysis

Background: Intraductal papillary mucinous neoplasms (IPMNs) are precancerous lesions with a well-described adenoma-carcinoma sequence. Although the risk of malignant transformation has been well studied, data on trends in long-term survival and important prognostic factors associated with survival in malignant IPMN are lacking. Methods: The Surveillance, Epidemiology, and End Results (SEER) database was queried to identify patients with confirmed malignant IPMN based upon pathologic diagnosis or radiographic evidence concerning for malignant potential. Median survival and age-adjusted incidence were calculated. Cox proportional hazard regression was used to determine independent mortality factors. Results: Based upon the SEER database query, 2651 patients were diagnosed with malignant IPMN between 1990 and 2010. The age-adjusted incidence of IPMN in 1990 was 0.361 per 100 000 persons (95% confidence interval [CI]: 0.285-0.451) with a steady decline observed through 2010 (0.135 per 100 000 persons, 95% CI: 0.098-0.186). A total of 564 patients (21.3%) underwent a surgical procedure, though the number of patients who underwent surgery from 1990 to 2010 also decreased (1990-1995, n = 132 to 2006-2010, n = 96, respectively). The overall median survival was 4 months and remained relatively stable from 1990 to 2010. Performance of surgery (HR: 0.45, 95% CI: 0.40-0.53, P < 0.001) was associated with a decreased risk of death. Conclusion: A significant decrease in the incidence of malignant IPMN was seen from 1990 to 2010. There was also no improvement observed in long-term survival. The small percentage of eligible cases receiving surgical treatment suggests that there is room for further improvement in survival, with increased utilization of surgery.