title: Prognostic impact of venous invasion in stage IB node-negative gastric cancer.
abstract: BACKGROUND
  Little is known about risk factors for recurrence in stage IB gastric cancer without lymph node metastasis. The aims of this study were to determine prognostic factors associated with long-term survival and to clarify patterns of recurrence.
  
  
  METHODS
  We retrospectively reviewed the medical records of 130 patients with primary gastric cancer who underwent gastrectomy at Kitasato University East Hospital from 2001 through 2010 and analyzed clinicopathological characteristics associated with survival and patterns of recurrence.
  
  
  RESULTS
  Of the 130 patients, 12 (9.2%) had recurrence, among whom 10 (83%) patients died. Four patients (3.1%) died of other diseases. The 5-year overall survival rate was 89%. Of the 12 patients with recurrence, 7 (58%) had liver metastasis, 3 (25%) had distant lymph-node metastasis, 2 (17%) had peritoneal dissemination, and 1 (8.3%) had locoregional recurrence. Patients with tumors more than 5 cm in diameter tended to have recurrence within 1 year. Patients who had recurrence more than 2 years after surgery tended to survive for longer than 5 years after recurrence. Moderate or marked venous invasion (v2 or v3) and age >65 years were significantly associated with relapse-free and overall survival on univariate analysis. On multivariate analysis, the only independent prognostic factor for relapse-free and overall survival was venous invasion.
  
  
  CONCLUSIONS
  Moderate or marked venous invasion (v2 or v3) is an independent predictor of relapse-free and overall survival in stage IB node-negative gastric cancer. Postoperative adjuvant chemotherapy, currently not given to this subgroup of patients, may improve the outcomes of patients with stage IB node-negative gastric cancer, particularly when accompanied by venous invasion.
authors.affiliation: Department of Surgery, School of Medicine, Kitasato University, Kitasato1-15-1, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan.
authors.forename: Ippeita
authors.initials: I
authors.lastname: Araki
authors.forename: Kei
authors.initials: K
authors.lastname: Hosoda
authors.forename: Keishi
authors.initials: K
authors.lastname: Yamashita
authors.forename: Natsuya
authors.initials: N
authors.lastname: Katada
authors.forename: Shinichi
authors.initials: S
authors.lastname: Sakuramoto
authors.forename: Hiromitsu
authors.initials: H
authors.lastname: Moriya
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Mieno
authors.forename: Akira
authors.initials: A
authors.lastname: Ema
authors.forename: Shiro
authors.initials: S
authors.lastname: Kikuchi
authors.forename: Tetuo
authors.initials: T
authors.lastname: Mikami
authors.forename: Masahiko
authors.initials: M
authors.lastname: Watanabe
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008113:Liver Neoplasms / Q000401:mortality / Q000556:secondary* / Q000601:surgery; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D009367:Neoplasm Staging; D011379:Prognosis; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D015996:Survival Rate; D055815:Young Adult