title: The distance of tumor spread in the main pancreatic duct of an intraductal papillary-mucinous neoplasm: where to resect and how to predict it.
abstract: BACKGROUND
  The surgical decision regarding where to resect the pancreas is an important judgement that is directly linked to the surgical procedure. An appropriate surgical margin to resect intraductal papillary-mucinous neoplasm (IPMN) of the pancreas based on the distance of tumor spread (DTS) in the main pancreatic duct has not been adequately documented. We analyzed the appropriate surgical margin based on the DTS in the main pancreatic duct of IPMN and the positive rate at the pancreatic cut end margin.
  
  
  METHODS
  Forty patients with main duct- or mixed-type IPMN diagnosed histopathologically who underwent surgery at Tokai University Hospital between 1991 and 2008 were retrospectively analyzed. The resection line was determined to achieve a 2-cm surgical margin in patients with main duct- or mixed-type IPMN and as limited a resection as possible to remove the dilated branch duct in patients with branch duct-type IPMN according to macroscopic type. The dysplastic state of the epithelium was judged as positive for carcinoma in situ (high-grade dysplasia) or adenoma (very low to moderate dysplasia) and judged as negative for hyperplasia or normal.
  
  
  RESULTS
  The mean DTS in the main pancreatic duct was 41.6 +/- 30.0 mm, and that of the distance of tumor absence was 13.6 +/- 12.4 mm. The positive rate at the pancreatic cut end margin in frozen sections was 29.7%. The final positive rate at the pancreatic cut end margin was 26.2%. There has been no evidence of local recurrence in the remnant pancreas. DTS in the main pancreatic duct of IPMN was correlated with the maximum diameter of the duct (R = 0.678).
  
  
  CONCLUSIONS
  Distance of tumor spread offered important insights about the appropriate site to resect the pancreas and the positive rate at the cut end margin in IPMN.
authors: Department of Surgery, Tokai University School of Medicine, Isehara, Kanagawa 259-1193, Japan. okada@is.icc.u-tokai.ac.jp
authors: Ken-ichi
authors: K
authors: Okada
authors: Toshihide
authors: T
authors: Imaizumi
authors: Kenichi
authors: K
authors: Hirabayashi
authors: Masahiro
authors: M
authors: Matsuyama
authors: Naoki
authors: N
authors: Yazawa
authors: Shoichi
authors: S
authors: Dowaki
authors: Kosuke
authors: K
authors: Tobita
authors: Yasuo
authors: Y
authors: Ohtani
authors: Yoshiaki
authors: Y
authors: Kawaguchi
authors: Makiko
authors: M
authors: Tanaka
authors: Sadaki
authors: S
authors: Inokuchi
authors: Hiroyasu
authors: H
authors: Makuuchi
mesh_terms: D002288:Adenocarcinoma, Mucinous / Q000473:pathology* / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D021441:Carcinoma, Pancreatic Ductal / Q000473:pathology* / Q000601:surgery; D002291:Carcinoma, Papillary / Q000473:pathology* / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D010180:Pancreatectomy / Q000379:methods*; D010190:Pancreatic Neoplasms / Q000473:pathology* / Q000601:surgery; D012189:Retrospective Studies; D016896:Treatment Outcome