title: Predictive factors for lymph node metastasis in additional gastrectomy after endoscopic resection of cT1aN0 gastric cancer.
abstract: OBJECTIVE
  Endoscopic therapy for clinical T1aN0 (cT1aN0) gastric cancer is an excellent therapeutic strategy; however, pathological lymph node metastasis (LNM) occasionally occurs. Patients who have a potential for LNM are subject to additional gastrectomy. Our aim was to identify predictors of LNM in additional gastrectomy.
  
  
  METHODS
  One hundred and twelve cT1aN0 gastric cancer patients undergoing additional gastrectomy after endoscopic resection were identified between 1997 and 2013. Predictors for LNM were initially selected by a univariate analysis and applied to a multivariate analysis.
  
  
  RESULTS
  (1) Twelve patients (10.7 %) had LNM following additional gastrectomy. (2) Clinicopathological factors significantly associated with LNM were the depth of invasion (SM2 or deeper, designated as SM2) (p = 0.0018) and rigorous lymphatic invasion (ly2,3) (p < 0.001). (3) The univariate predictors for LNM were applied to the multivariate logistic regression model, and SM2 (p = 0.0027) and ly2,3 (p = 0.0028) remained significant predictors. (4) When classified into 2 × 2 subgroups, the predictability for LNM was as follows: SM2 plus ly2,3 (46.7 %), SM2 plus ly0,1 (10.0 %), M,SM1 plus ly2,3 (0 %), and M,SM1 plus ly0,1 (0 %).
  
  
  CONCLUSIONS
  In cT1aN0 gastric cancer patients, both SM2 and ly2,3 are significant predictors for LNM that may be important as references for additional gastrectomy after endoscopic resection.
authors.affiliation: Department of Surgery, Kitasato University School of Medicine, Kitasato 1-15-1, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Ishii
authors.affiliation: Department of Surgery, Kitasato University School of Medicine, Kitasato 1-15-1, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan.
authors.forename: Keishi
authors.initials: K
authors.lastname: Yamashita
authors.affiliation: Department of Surgery, Kitasato University School of Medicine, Kitasato 1-15-1, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kato
authors.affiliation: Department of Surgery, Kitasato University School of Medicine, Kitasato 1-15-1, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan.
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Nishizawa
authors.affiliation: Department of Surgery, Kitasato University School of Medicine, Kitasato 1-15-1, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Ushiku
authors.affiliation: Department of Surgery, Kitasato University School of Medicine, Kitasato 1-15-1, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Mieno
authors.affiliation: Department of Surgery, Kitasato University School of Medicine, Kitasato 1-15-1, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan.
authors.forename: Hiromitu
authors.initials: H
authors.lastname: Moriya
authors.affiliation: Department of Surgery, Kitasato University School of Medicine, Kitasato 1-15-1, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan.
authors.forename: Kei
authors.initials: K
authors.lastname: Hosoda
authors.affiliation: Department of Surgery, Kitasato University School of Medicine, Kitasato 1-15-1, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan.
authors.forename: Natuya
authors.initials: N
authors.lastname: Katada
authors.affiliation: Department of Surgery, Kitasato University School of Medicine, Kitasato 1-15-1, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan.
authors.forename: Shiro
authors.initials: S
authors.lastname: Kikuchi
authors.affiliation: Department of Gastroenterology, Kitasato University School of Medicine, Kitasato 1-15-1, Minami-ku, Sagamihara, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tanabe
authors.affiliation: Department of Gastroenterology, Kitasato University School of Medicine, Kitasato 1-15-1, Minami-ku, Sagamihara, Japan.
authors.forename: Wasaburo
authors.initials: W
authors.lastname: Koizumi
authors.affiliation: Department of Pathology, Kitasato University School of Medicine, Kitasato 1-15-1, Minami-ku, Sagamihara, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Saegusa
authors.affiliation: Department of Surgery, Kitasato University School of Medicine, Kitasato 1-15-1, Minami-ku, Sagamihara, Kanagawa, 252-0374, Japan. gekaw@med.kitasato-u.ac.jp.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Watanabe
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D005260:Female; D005544:Forecasting; D005743:Gastrectomy / Q000379:methods; D005773:Gastroscopy; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011247:Pregnancy; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery*; D015996:Survival Rate; D016896:Treatment Outcome
keywords: Additional gastrectomy; Endoscopic resection; Lymph node metastasis; SM2; ly2,3