title: Additive endoscopic resection may be sufficient for patients with a positive lateral margin after endoscopic resection of early gastric cancer.
abstract: OBJECTIVE
  No well-established treatment strategies exist for lateral margin positivity (LM+) alone after endoscopic resection (ER) of early gastric cancer (EGC). Thus, we aimed to clarify a treatment strategy for non-curative resection (non-CR) with LM+ alone after ER in EGC.
  
  
  METHODS
  Among 2065 patients with EGC treated by ER, 76 (3.6%) with only LM+ after non-CR of EGC were reviewed retrospectively. Of these, 28 underwent gastrectomy, 25 underwent argon plasma coagulation (APC), and 23 underwent repeat ER (re-ER). We analyzed the clinicopathologic characteristics of all patients and compared those who underwent additive surgery, APC, or re-ER.
  
  
  RESULTS
  Of the 76 patients, 28 (36.8%) fulfilled the absolute criteria and 48 (63.2%) the expanded criteria for ER. Among the latter patients, the proportion undergoing additive surgery was 75.0%, higher than that of patients in the former group (P = .014). Residual cancer cells were observed in 70.6% of patients after additive surgery or re-ER. Residual cancer cells were observed significantly more often in patients with undifferentiated-type than in those with differentiated-type EGC (P = .02). However, no lymph node metastasis was observed in any patient after additive surgery.
  
  
  CONCLUSIONS
  Our results suggest that endoscopic treatment may be a sufficient additive therapy for patients with LM+ alone after ER, irrespective of whether the absolute or expanded ER criteria are used. However, as complete ablation of remnant cells cannot be guaranteed, re-ER is a better additive treatment than APC.
authors.affiliation: Department of Internal Medicine, Institute of Gastroenterology, Seoul, Korea; Gangnam Severance Hospital, Seoul, Korea; Digestive Disease Center and Research Institute, Soonchunhyang University School of Medicine, Bucheon, Korea.
authors.forename: Hae Won
authors.initials: HW
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Institute of Gastroenterology, Seoul, Korea; Gangnam Severance Hospital, Seoul, Korea; Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jie-Hyun
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Institute of Gastroenterology, Seoul, Korea; Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jun Chul
authors.initials: JC
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Institute of Gastroenterology, Seoul, Korea; Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Mi Young
authors.initials: MY
authors.lastname: Jeon
authors.affiliation: Department of Internal Medicine, Institute of Gastroenterology, Seoul, Korea; Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Yong Chan
authors.initials: YC
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Institute of Gastroenterology, Seoul, Korea; Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sang Kil
authors.initials: SK
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Institute of Gastroenterology, Seoul, Korea; Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sung Kwan
authors.initials: SK
authors.lastname: Shin
authors.affiliation: Department of Internal Medicine, Institute of Gastroenterology, Seoul, Korea; Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Hyun Soo
authors.initials: HS
authors.lastname: Chung
authors.affiliation: Department of Surgery, Division of Gastroenterology, Seoul, Korea; Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sung Hoon
authors.initials: SH
authors.lastname: Noh
authors.affiliation: Department of Surgery, Division of Gastroenterology, Seoul, Korea; Gangnam Severance Hospital, Seoul, Korea; Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jong Won
authors.initials: JW
authors.lastname: Kim
authors.affiliation: Department of Surgery, Division of Gastroenterology, Seoul, Korea; Gangnam Severance Hospital, Seoul, Korea; Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Seung Ho
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Department of Internal Medicine, Institute of Gastroenterology, Seoul, Korea; Gangnam Severance Hospital, Seoul, Korea; Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jae Jun
authors.initials: JJ
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Institute of Gastroenterology, Seoul, Korea; Gangnam Severance Hospital, Seoul, Korea; Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Young Hoon
authors.initials: YH
authors.lastname: Youn
authors.affiliation: Department of Internal Medicine, Institute of Gastroenterology, Seoul, Korea; Gangnam Severance Hospital, Seoul, Korea; Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Hyojin
authors.initials: H
authors.lastname: Park
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000601:surgery*; D000368:Aged; D057908:Argon Plasma Coagulation; D018279:Carcinoma, Signet Ring Cell / Q000473:pathology / Q000601:surgery*; D005260:Female; D005743:Gastrectomy; D005773:Gastroscopy / Q000379:methods*; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D000072662:Margins of Excision; D008875:Middle Aged; D009367:Neoplasm Staging; D018365:Neoplasm, Residual; D012086:Reoperation; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000473:pathology / Q000601:surgery*