title: Methylene blue-assisted technique for harvesting lymph nodes after radical surgery for gastric cancer: a prospective randomized phase III study.
abstract: BACKGROUND
  This randomized Phase III trial will evaluate whether the methylene blue-assisted technique is efficient for harvesting lymph nodes after radical surgery for gastric cancer.
  
  
  METHODS
  Patients that undergo distal or total gastrectomy with radical nodal dissection will be randomly assigned to Group A: the standard group, the lymph nodes (LNs) will be harvested from the fresh specimen immediately after surgery, or Group B: the methylene blue-assisted group, where the LNs will be harvested from specimens fixed with 10% buffered formalin with methylene blue for 48 hours after surgery. The primary endpoint is the ratio of the number of the harvested LNs per time (minute). The secondary endpoint is the number of harvested LNs. A 25% reduction in the ratio of harvested lymph-node/time (minute) was determined to be necessary for this test treatment, considering the balance between the cost and benefit. Retrospective data was used to estimate the ratio of the number of the harvested LNs per time (minute) to be 40/30 minutes in Group A. A 25% risk reduction and a rate of 40/22.5 minutes is expected in Group B. Therefore, the sample size required ensuring a two-sided alpha error of 5% and statistical power of 80% is 52 patients, with 26 patients per arm. The number of patients to be accrued was set at 60 in total, due to the likelihood of enrolling ineligible patients.
  
  
  BACKGROUND
  UMIN000008624.
authors.forename: Toru
authors.initials: T
authors.lastname: Aoyama
authors.affiliation: Department of Gastrointestinal Surgery, Kanagawa Cancer Center, 1-1-2 Nakao, Asahi-ku, Yokohama 241-0815, Japan. yoshikawat@kcch.jp.
authors.forename: Takaki
authors.initials: T
authors.lastname: Yoshikawa
authors.forename: Satoshi
authors.initials: S
authors.lastname: Morita
authors.forename: Junya
authors.initials: J
authors.lastname: Shirai
authors.forename: Hirohito
authors.initials: H
authors.lastname: Fujikawa
authors.forename: Kenichi
authors.initials: K
authors.lastname: Iwasaki
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Hayashi
authors.forename: Takashi
authors.initials: T
authors.lastname: Ogata
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Cho
authors.forename: Norio
authors.initials: N
authors.lastname: Yukawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Oshima
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Rino
authors.forename: Munetaka
authors.initials: M
authors.lastname: Masuda
authors.forename: Akira
authors.initials: A
authors.lastname: Tsuburaya
mesh_terms: D002985:Clinical Protocols; D006801:Humans; D008197:Lymph Node Excision / Q000379:methods; D008198:Lymph Nodes / Q000473:pathology*; D008751:Methylene Blue; D013274:Stomach Neoplasms / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery*
chemical_list: D008751:Methylene Blue