Roch AM, Ceppa EP, Al-Haddad MA, DeWitt JM, House MG, Zyromski NJ, Nakeeb A, Schmidt CM. The natural history of main duct-involved, mixed-type intraductal papillary mucinous neoplasm: parameters predictive of progression. Ann Surg. 2014 Oct; 260(4):680-8; discussion 688-90.