title: The prognosis of intraductal papillary mucinous tumors of the pancreas.
abstract: OBJECTIVE
  Intraductal papillary mucinous tumors of the pancreas have been recognized as a distinct clinical entity. However, their biological behavior has not been clearly defined. The aim of this study was to examine the prognosis of this tumor, to clarify the biological behavior and determine the most appropriate treatment.
  
  
  METHODS
  Correlations between prognosis of operated cases and histopathologic features were investigated.
  
  
  RESULTS
  In 105 patients with characteristic clinical features of intraductal papillary mucinous tumors, the lesions were classified as hyperplasias in 21%, intraductal tumors in 48% and invasive carcinomas in 31%. Minimal invasion was apparent in 25%, lymph node metastasis in 21%, and fistula formation in 31% of the invasive lesions. Non-invasive and minimally invasive intraductal papillary mucinous tumors were essentially free from risk of tumor recurrence. Other invasive intraductal papillary mucinous tumors showed a significantly poor prognosis.
  
  
  CONCLUSIONS
  Because of the variation in pathological characteristics, patient outcome and the possibility of differential diagnosis, the treatment might be recommended as follows: the case of hyperplasia can be followed-up with close surveillance. Non-invasive and minimally invasive intraductal papillary mucinous tumors should be operated with function-preserving minimal pancreatectomy. For patients with invasive intraductal papillary mucinous tumors evident with preoperative imaging modalities, radical operations with lymph node dissection might be needed.
authors.affiliation: Department of Gastroenterology, Aichi Cancer Center Hospital, Nagoya, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yamao
authors.forename: K
authors.initials: K
authors.lastname: Ohashi
authors.forename: T
authors.initials: T
authors.lastname: Nakamura
authors.forename: T
authors.initials: T
authors.lastname: Suzuki
authors.forename: Y
authors.initials: Y
authors.lastname: Shimizu
authors.forename: Y
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Y
authors.initials: Y
authors.lastname: Horibe
authors.forename: A
authors.initials: A
authors.lastname: Yanagisawa
authors.forename: A
authors.initials: A
authors.lastname: Nakao
authors.forename: Y
authors.initials: Y
authors.lastname: Nimuara
authors.forename: Y
authors.initials: Y
authors.lastname: Naito
authors.forename: T
authors.initials: T
authors.lastname: Hayakawa
mesh_terms: D000231:Adenocarcinoma, Papillary / Q000473:pathology* / Q000601:surgery; D000368:Aged; D021441:Carcinoma, Pancreatic Ductal / Q000473:pathology* / Q000601:surgery; D018282:Cystadenocarcinoma, Mucinous / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000473:pathology* / Q000601:surgery; D011379:Prognosis; D018709:Statistics, Nonparametric; D016019:Survival Analysis