title: Lymphoepithelioma-like carcinoma: a distinct type of gastric cancer.
abstract: BACKGROUND
  Lymphoepithelioma-like carcinoma (LELC) is a rare type of gastric carcinoma and has histologic features of intense lymphocytic infiltration. In this study, we attempted to analyze the clinicopathologic characteristics and survival outcome of patients with LELC compared with those with non-lymphoepithelioma-like carcinoma (NLELC).
  
  
  METHODS
  We studied 4282 patients who underwent gastrectomies to treat gastric cancer at the Department of Surgery of the Samsung Medical Center in Seoul, between January 2008 and December 2010. The clinicopathologic features and clinical outcomes of patients with LELC (n = 46) were compared with those with NLELC (n = 4236). In situ hybridization for Epstein-Barr virus (EBV) positivity was performed on the tissue of patients with LELC (n = 46) and NLELC (n = 1247).
  
  
  RESULTS
  The patients with LELC are male predominant and had more upper locations, more indeterminate Lauren classifications, lower T stages, less lymphatic invasion, and more positive EBV in situ hybridization compared with those of the NLELC group (80.4% versus 6.5%). Age, histologic type, Lauren type, the location of the tumor, the depth of the invasion, lymph node metastasis, and venous invasion were independent prognostic factors; however, the LELC type itself was not predictive of outcome. The 5-y survival rate of the LELC group (97.7%) was better than that of the NLELC group (89.4%); however, this difference was not statistically significant (P = 0.127).
  
  
  CONCLUSIONS
  The results of our study suggest that LELC is a less advanced disease than NLELC in terms of depth of invasion and lymphatic invasion at diagnosis. However, our study does not examine LELC as an independent prognostic factor of gastric cancer. Further studies are needed to explore its associations with EBV and a distinct pathway of carcinogenesis from NLELC.
authors.affiliation: Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Sungmin
authors.initials: S
authors.lastname: Park
authors.affiliation: Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. Electronic address: mingew.choi@samsung.com.
authors.forename: Min-Gew
authors.initials: MG
authors.lastname: Choi
authors.affiliation: Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Kyoung-Mee
authors.initials: KM
authors.lastname: Kim
authors.affiliation: Biostatistics and Clinical Epidemiology Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Hye Seung
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Biostatistics and Clinical Epidemiology Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Sin-Ho
authors.initials: SH
authors.lastname: Jung
authors.affiliation: Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jun Ho
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jae Hyung
authors.initials: JH
authors.lastname: Noh
authors.affiliation: Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Tae Sung
authors.initials: TS
authors.lastname: Sohn
authors.affiliation: Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jae Moon
authors.initials: JM
authors.lastname: Bae
authors.affiliation: Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Sung
authors.initials: S
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000276:immunology / Q000401:mortality / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008214:Lymphocytes; D008297:Male; D008875:Middle Aged; D056910:Republic of Korea / Q000453:epidemiology; D013270:Stomach / Q000276:immunology / Q000473:pathology*; D013274:Stomach Neoplasms / Q000276:immunology / Q000401:mortality / Q000473:pathology*
keywords: Clinicopathologic features; Epstein–Barr virus; Gastric cancer; Lymphoepithelioma-like carcinoma; Prognosis