title: Is endoscopic resection an alternative to surgery for early low-risk submucosal gastric cancers: analysis of a large surgical database.
abstract: BACKGROUND
  Although endoscopic resection (ER) for early gastric cancers (EGCs) has become popular with the development of endoscopic instruments and skillful endoscopists, the risk of lymph node metastasis (LNM) is still an obstacle in performing ER. In this study, we aimed to identify the risk factors of LNM and validated the expanded criteria, with the goal of suggesting modified criteria for ER in submucosal EGCs.
  
  
  METHODS
  Of patients who underwent gastrectomy with LN dissection and were diagnosed as EGCs with depth of invasion such as sm1, sm2 or ≤ 500 μm from 1999 to 2008, 318 EGCs with submucosal invasion ≤ 500 μm were enrolled through pathologic evaluations. To identify the risk factors of LNM, a multivariate analysis of clinicopathologic factors was performed. By combining the independent risk factors of LNM, the risk of LNM was analyzed.
  
  
  RESULTS
  LNM were detected in 35 cases (11.0 %). Tumors >30 mm in size and with lymphatic invasion were identified as an independent risk factor for LNM in EGCs with depth of invasion ≤ 500 μm. Among 94 cases meeting the expanded criteria, two cases (2.1 %) were found to have LNM. Based on the submucosal invasion <300 μm, there was no LNM in EGCs with a size ≤ 30 mm and no lymphovascular invasion, regardless of differentiation grade.
  
  
  CONCLUSIONS
  To exclude the possibility of LNM, applying the modified criteria based on the submucosal invasion <300 μm in performing ER might be worthwhile.
authors.affiliation: Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea, chunghyun.tae@gmail.com.
authors.forename: Chung Hyun
authors.initials: CH
authors.lastname: Tae
authors.forename: Roos E
authors.initials: RE
authors.lastname: Pouw
authors.forename: Lucas C
authors.initials: LC
authors.lastname: Duits
authors.forename: Young Kyung
authors.initials: YK
authors.lastname: Sung
authors.forename: Byung-Hoon
authors.initials: BH
authors.lastname: Min
authors.forename: Jun Haeng
authors.initials: JH
authors.lastname: Lee
authors.forename: Poong-Lyul
authors.initials: PL
authors.lastname: Rhee
authors.forename: Kyoung-Mee
authors.initials: KM
authors.lastname: Kim
authors.forename: Jacques J G H M
authors.initials: JJ
authors.lastname: Bergman
authors.forename: Jae J
authors.initials: JJ
authors.lastname: Kim
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology* / Q000601:surgery*; D004210:Dissection; D055088:Early Detection of Cancer; D005260:Female; D005743:Gastrectomy; D005753:Gastric Mucosa / Q000473:pathology* / Q000601:surgery*; D005773:Gastroscopy / Q000379:methods*; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009361:Neoplasm Invasiveness; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000473:pathology* / Q000601:surgery*