Intraductal papillary mucinous tumors of the pancreas: incidence, clinical findings and natural history.

Intraductal papillary-mucinous tumors of the pancreas are a category of recently described tumors of the exocrine pancreas. They were reported for the first time in 1982 [1] when Ohashi et al., based on the findings of four cases of mucous secreting pancreatic cancer, theorized that those cases belonged to a group of tumors with different features with respect to common pancreatic cancer. Some anecdotal reports of variably termed mucinous pancreatic tumors appeared in the subsequent ten years, but the absence of a uniform definition to identify these neoplasms hampered their characterization as a specific group. In 1994, Sessa et al. proposed calling the group of neoplasms characterized by intraductal papillary growth of mucin producing, hypersecreting, columnar cells “intraductal papillary-mucinous tumors (IPMTs)” [2]. Since that time, the number of citations of IPMT in the medical literature has constantly increased.