title: Treatment guidelines for branch duct type intraductal papillary mucinous neoplasms of the pancreas: when can we operate or observe?
abstract: BACKGROUND
  The objectives of this study were to investigate the clinicopathological features of branch intraductal papillary mucinous neoplasm (IPMN) and to determine safe criteria for its observation. Most clinicians agree that surgical resection is required to treat main duct-type IPMN because of its high malignancy rate. However, no definite treatment guideline (with respect to surgery or observation) has been issued on the management of branch duct type IPMN.
  
  
  METHODS
  We retrospectively reviewed the clinicopathological data of 138 patients who underwent operations for IPMN between 1993 and 2006 at five institutes in Korea.
  
  
  RESULTS
  Of 138 patients (mean age, 60.6 years; 87 men, 51 women), 76 underwent pancreatoduodenectomy, 39 distal pancreatectomy, 4 total pancreatectomy, and 20 limited pancreatic resection. There were 112 benign cases: 47 adenoma, 63 borderline cases, and 26 malignant cases, with 9 of these being noninvasive and 17 invasive. By univariate analysis, tumor size and the presence of a mural nodule were identified as meaningful predictors of malignancy. By receiver operating characteristic curve analysis, a tumor size of >2 cm was found to be the most valuable predictor of malignancy. When cases were classified according to tumor size and the presence of a mural nodule, the malignancy rate for a tumor </=2 cm without a mural nodule was 9.2%, for a tumor of </=2 cm plus a mural nodule was 25%, and for other conditions such as tumor >2 cm, >25%.
  
  
  CONCLUSIONS
  Many branch duct IPMNs are malignant. Surgical treatment is recommended, except in cases that are strongly suspected to be benign or cases that present a high operative risk. Observation is only recommended in patients with a tumor size of </=2 cm without a mural nodule.
authors.affiliation: Department of Surgery, Seoul National University College of Medicine, 28 Yongon-dong, Chongno-gu, Seoul, South Korea. sunkim@plaza.snu.ac.kr
authors.forename: Jin-Young
authors.initials: JY
authors.lastname: Jang
authors.forename: Sun-Whe
authors.initials: SW
authors.lastname: Kim
authors.forename: Seung Eun
authors.initials: SE
authors.lastname: Lee
authors.forename: Sung Hoon
authors.initials: SH
authors.lastname: Yang
authors.forename: Kuhn Uk
authors.initials: KU
authors.lastname: Lee
authors.forename: Young Joo
authors.initials: YJ
authors.lastname: Lee
authors.forename: Song Chul
authors.initials: SC
authors.lastname: Kim
authors.forename: Duck Jong
authors.initials: DJ
authors.lastname: Han
authors.forename: Dong Wook
authors.initials: DW
authors.lastname: Choi
authors.forename: Seong Ho
authors.initials: SH
authors.lastname: Choi
authors.forename: Jin Seok
authors.initials: JS
authors.lastname: Heo
authors.forename: Baik Hwan
authors.initials: BH
authors.lastname: Cho
authors.forename: Hee Chul
authors.initials: HC
authors.lastname: Yu
authors.forename: Dong Sup
authors.initials: DS
authors.lastname: Yoon
authors.forename: Woo Jung
authors.initials: WJ
authors.lastname: Lee
authors.forename: Hee-Eun
authors.initials: HE
authors.lastname: Lee
authors.forename: Gyeong Hoon
authors.initials: GH
authors.lastname: Kang
authors.forename: Jeong Min
authors.initials: JM
authors.lastname: Lee
mesh_terms: D002288:Adenocarcinoma, Mucinous / Q000473:pathology / Q000601:surgery*; D000236:Adenoma / Q000473:pathology / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D021441:Carcinoma, Pancreatic Ductal / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D010180:Pancreatectomy; D010190:Pancreatic Neoplasms / Q000473:pathology / Q000601:surgery*; D016577:Pancreaticoduodenectomy; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate