title: Omentum-preserving gastrectomy for advanced gastric cancer: a propensity-matched retrospective cohort study.
abstract: OBJECTIVE
  We clarified the impact of omentectomy for advanced gastric cancer on patient survival from the surgical results of a high-volume center in Japan.
  
  
  METHODS
  Patients who received curative gastrectomy were divided into two groups based on whether they underwent omentectomy. The propensity score-matching method was used to assemble a well-balanced cohort, and relapse-free survival and the pattern of recurrence were compared.
  
  
  RESULTS
  For this study, 330 patients who fulfilled the inclusion criteria participated and were divided into two groups: group R, patients who received omentectomy, and group P, patients who received omentum-preserving gastrectomy. After performing score-matching, 196 patients were selected. The 3- and 5-year relapse-free survival rates were 72.9% (95% confidence interval, 64.1-81.7) and 66.2% (56.6-75.8%) in group R, and 76.7% (67.9-81.2) and 67.3% (55.1-79.5) in group P, which were not significantly different (P = 0.750). Regarding sites of relapses, no differences were observed between the groups (P = 0.863).
  
  
  CONCLUSIONS
  In this series, omentum-preserving gastrectomy for advanced gastric cancer did not increase the peritoneal relapse rate or affect patient survival compared to conventional gastrectomy. The non-inferiority of the omission of omentectomy should be evaluated by a randomized controlled trial.
authors.affiliation: Department of Surgery, Yokohama City University Medical Center, Urafune-cho 4-57, Minami-ku, Yokohama, 232-0024, Japan. hsgws@yokohama-cu.ac.jp
authors.forename: Shinichi
authors.initials: S
authors.lastname: Hasegawa
authors.forename: Chikara
authors.initials: C
authors.lastname: Kunisaki
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Ono
authors.forename: Takashi
authors.initials: T
authors.lastname: Oshima
authors.forename: Shoichi
authors.initials: S
authors.lastname: Fujii
authors.forename: Masataka
authors.initials: M
authors.lastname: Taguri
authors.forename: Satoshi
authors.initials: S
authors.lastname: Morita
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Sato
authors.forename: Roppei
authors.initials: R
authors.lastname: Yamada
authors.forename: Norio
authors.initials: N
authors.lastname: Yukawa
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Rino
authors.forename: Munetaka
authors.initials: M
authors.lastname: Masuda
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D018572:Disease-Free Survival; D005260:Female; D005743:Gastrectomy / Q000379:methods*; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009852:Omentum / Q000601:surgery*; D059351:Organ Sparing Treatments / Q000379:methods*; D010529:Peritoneal Cavity / Q000473:pathology; D057216:Propensity Score; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000473:pathology / Q000601:surgery*; D015996:Survival Rate