title: Non-neoplastic pathology results after endoscopic submucosal dissection for gastric epithelial dysplasia or early gastric cancer.
abstract: OBJECTIVE
  Endoscopists sometimes face paradoxical cases in which the endoscopic submucosal dissection (ESD) specimen reveals a non-neoplastic pathology result. The aims of the study were to determine the reasons for such results, and to compare the endoscopic characteristics of non-neoplastic and conventional neoplastic pathology groups after ESD.
  
  
  METHODS
  A total of 1186 gastric ESDs performed between February 2005 and December 2011 were retrospectively reviewed. The ESD specimens included 52 (4.4 %) that were confirmed as negative or indefinite for neoplasia. Patient characteristics and endoscopic and pathological data were reviewed and compared.
  
  
  RESULTS
  Non-neoplastic pathology after ESD was due to complete removal of the lesion at biopsy in 45 cases (86.5 %), pathology overestimation in 5 (9.6 %), and incorrect localization of the original tumor with subsequent ESD performed at the wrong site in 2 (3.8 %). The mean length and surface area of the non-neoplastic lesions were 9.2 ± 2.6 mm and 49.6 ± 23.6 mm (2), respectively. Mean sampling ratios were 3.0 ± 1.5 mm/fragment and 16.3 ± 10.0 mm(2)/fragment. Compared with 1134 cases confirmed as neoplastic on the final ESD specimen, non-neoplastic cases showed a significantly smaller tumor size and surface area, and lower sampling ratios in a logistic regression analysis adjusted for potential confounders (P < 0.001 for all).
  
  
  CONCLUSIONS
  Complete lesion removal by biopsy, pathology overestimation, and incorrect localization of the original tumor with subsequent ESD at the wrong site were the main reasons for non-neoplastic results after ESD. Small tumor size and surface area, and low sampling ratios were associated with non-neoplastic pathology results after ESD.
authors: Department of Gastroenterology, Ajou University School of Medicine, Suwon, South Korea.
authors: Min Jae
authors: MJ
authors: Yang
authors: Department of Gastroenterology, Ajou University School of Medicine, Suwon, South Korea.
authors: Sung Jae
authors: SJ
authors: Shin
authors: Department of Gastroenterology, Ajou University School of Medicine, Suwon, South Korea.
authors: Ki Seong
authors: KS
authors: Lee
authors: Department of Gastroenterology, Ajou University School of Medicine, Suwon, South Korea.
authors: Kee Myung
authors: KM
authors: Lee
authors: Department of Gastroenterology, Ajou University School of Medicine, Suwon, South Korea.
authors: Sun Gyo
authors: SG
authors: Lim
authors: Department of Gastroenterology, Ajou University School of Medicine, Suwon, South Korea.
authors: Joon Koo
authors: JK
authors: Kang
authors: Department of Gastroenterology, Ajou University School of Medicine, Suwon, South Korea.
authors: Jae Chul
authors: JC
authors: Hwang
authors: Department of Gastroenterology, Ajou University School of Medicine, Suwon, South Korea.
authors: Soon Sun
authors: SS
authors: Kim
authors: Department of Pathology, Ajou University School of Medicine, Suwon, South Korea.
authors: Dakeun
authors: D
authors: Lee
authors: Department of Gastroenterology, Ajou University School of Medicine, Suwon, South Korea.
authors: Joo-Sung
authors: JS
authors: Kim
authors: Department of Gastroenterology, Ajou University School of Medicine, Suwon, South Korea.
authors: Gil-Ho
authors: GH
authors: Lee
authors: Department of Gastroenterology, Ajou University School of Medicine, Suwon, South Korea.
authors: Han Seok
authors: HS
authors: Ryu
authors: Department of Gastroenterology, Ajou University School of Medicine, Suwon, South Korea.
authors: Byung Moo
authors: BM
authors: Yoo
authors: Department of Gastroenterology, Ajou University School of Medicine, Suwon, South Korea.
authors: Kwang Jae
authors: KJ
authors: Lee
authors: Department of Pathology, Ajou University School of Medicine, Suwon, South Korea.
authors: Young Bae
authors: YB
authors: Kim
authors: Department of Gastroenterology, Ajou University School of Medicine, Suwon, South Korea.
authors: Jin Hong
authors: JH
authors: Kim
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology* / Q000601:surgery; D000236:Adenoma / Q000473:pathology* / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004210:Dissection / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D005753:Gastric Mucosa / Q000473:pathology* / Q000601:surgery; D005773:Gastroscopy / Q000379:methods; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000473:pathology* / Q000601:surgery; D016896:Treatment Outcome