title: Incidence of extrapancreatic malignancies in patients with intraductal papillary mucinous neoplasms of the pancreas.
abstract: OBJECTIVE
  Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas have been reported to be associated with extrapancreatic malignancies, but there have been no prospective studies evaluating the incidence of extrapancreatic cancers in patients with IPMNs. In this study, the frequency of patients with IPMNs developing extrapancreatic cancers during follow-up was examined.
  
  
  METHODS
  642 patients with IPMNs were prospectively followed up for 4.8 years on average. They underwent clinical examination at least twice a year. The incidence of the observed extrapancreatic malignancies was compared with the expected incidence of the age- and gender-matched general Japanese population based on the Vital Statistics of Japan.
  
  
  RESULTS
  40 extrapancreatic cancers developed in 39 patients during follow-up (1.3% per year). The most common malignancies were hepatocellular (n=7), colorectal (n=6), gastric (n=6), lung (n=5) and prostate cancers (n=4). The calculated standardised incidence rate of each of the malignancies was not significant, as follows: hepatocellular 2.17 (95% CI 0.87 to 4.47), colorectal 1.02 (0.37 to 2.21), gastric 0.76 (0.28 to 1.66), lung 0.75 (0.24 to 1.76) and prostate 1.00 (0.71 to 1.29). Pancreatic cancer was observed in 17 patients during the same period, with a standardised incidence rate of 10.7 (6.2 to 17.1).
  
  
  CONCLUSIONS
  The incidence of extrapancreatic malignancies in patients with IPMNs was similar to that in the general population, whereas the incidence of pancreatic cancers was significantly high. Intraductal papillary mucinous neoplasms are not associated with systemic carcinogenesis except for pancreatic cancer.
authors.affiliation: Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
authors.forename: Kazumichi
authors.initials: K
authors.lastname: Kawakubo
authors.forename: Minoru
authors.initials: M
authors.lastname: Tada
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Isayama
authors.forename: Naoki
authors.initials: N
authors.lastname: Sasahira
authors.forename: Yousuke
authors.initials: Y
authors.lastname: Nakai
authors.forename: Keisuke
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Kogure
authors.forename: Takashi
authors.initials: T
authors.lastname: Sasaki
authors.forename: Kenji
authors.initials: K
authors.lastname: Hirano
authors.forename: Hideaki
authors.initials: H
authors.lastname: Ijichi
authors.forename: Keisuke
authors.initials: K
authors.lastname: Tateishi
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Yoshida
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Koike
mesh_terms: D002288:Adenocarcinoma, Mucinous / Q000453:epidemiology*; D000368:Aged; D021441:Carcinoma, Pancreatic Ductal / Q000453:epidemiology*; D002291:Carcinoma, Papillary / Q000453:epidemiology*; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary / Q000453:epidemiology; D016609:Neoplasms, Second Primary / Q000453:epidemiology*; D010190:Pancreatic Neoplasms / Q000453:epidemiology*