title: Additional surgery for non-curative resection after endoscopic submucosal dissection for gastric cancer: a retrospective analysis of 200 cases.
abstract: OBJECTIVE
  Endoscopic submucosal dissection is recommended for early gastric cancer with a low risk of lymph node metastasis. When the pathological findings do not meet the curative criteria; then, an additional gastrectomy with lymph node dissection is recommended. However, most cases have neither lymph node metastasis nor a local residual tumor during an additional surgery.
  
  
  METHODS
  This was a single-institutional retrospective cohort study, analyzing 200 patients who underwent an additional gastrectomy after non-curative endoscopic submucosal dissection from January 2005 to October 2015. We reviewed the patients' clinicopathological data and evaluated the predictors for the presence of a residual tumor.
  
  
  RESULTS
  Histopathology revealed lymph node metastasis in 15 patients (7.5 %) and a local residual tumor in 23 (11.5 %). A multivariable analysis revealed macroscopic findings (flat/elevated type) (p = 0.011, odds ratio = 4.63), lymphatic invasion (p < 0.0001, odds ratio = 14.2), and vascular invasion (p = 0.04, odds ratio = 4.00) to be predictors for lymph node metastasis. A positive vertical margin (p = 0.0027, odds ratio = 3.26) and horizontal margin (p = 0.0008, odds ratio = 5.74) were predictors for a local residual tumor. All cases with lymph node metastasis had lymphovascular invasion with at least one other non-curative factor.
  
  
  CONCLUSIONS
  The risk of a residual tumor can, therefore, be estimated based on the histopathology of endoscopic submucosal dissection samples. Lymphovascular invasion appears to be a pivotal predictor of lymph node metastasis.
authors.affiliation: Gastric Surgery Division, National Cancer Center Hospital East, 6-5-1, Kashiwanoha, Kashiwa, 277-8577, Chiba, Japan.|Course of Advanced Clinical Research of Cancer, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Sunagawa
authors.affiliation: Gastric Surgery Division, National Cancer Center Hospital East, 6-5-1, Kashiwanoha, Kashiwa, 277-8577, Chiba, Japan. takkinos@east.ncc.go.jp.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Kinoshita
authors.affiliation: Gastric Surgery Division, National Cancer Center Hospital East, 6-5-1, Kashiwanoha, Kashiwa, 277-8577, Chiba, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Kaito
authors.affiliation: Gastric Surgery Division, National Cancer Center Hospital East, 6-5-1, Kashiwanoha, Kashiwa, 277-8577, Chiba, Japan.
authors.forename: Hidehito
authors.initials: H
authors.lastname: Shibasaki
authors.affiliation: Endoscopy Division, Department of Gastroenterology, National Cancer Center Hospital East, 6-5-1, Kashiwanoha, Kashiwa, 277-8577, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kaneko
authors.affiliation: Division of Pathology, Exploratory Oncology Research and Clinical Trial Center, National Cancer Center Hospital East, 6-5-1, Kashiwanoha, Kashiwa, 277-8577, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ochiai
authors.affiliation: Exploratory Oncology Research and Clinical Trial Center, National Cancer Center, 6-5-1, Kashiwanoha, Kashiwa, 277-8577, Japan.|Course of Advanced Clinical Research of Cancer, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ohtsu
authors.affiliation: Gastric Surgery Division, National Cancer Center Hospital East, 6-5-1, Kashiwanoha, Kashiwa, 277-8577, Chiba, Japan.
authors.forename: Toshirou
authors.initials: T
authors.lastname: Nishida
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D016099:Endoscopy, Gastrointestinal; D005260:Female; D005743:Gastrectomy; D006801:Humans; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D018365:Neoplasm, Residual; D010166:Palliative Care; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000473:pathology* / Q000601:surgery*
keywords: Additional gastrectomy; Endoscopic submucosal dissection; Gastric cancer; Lymph node metastasis