title: Primary small cell carcinoma of the esophagus: clinicopathological study of 44 cases.
abstract: BACKGROUND
  Primary small cell carcinoma of the esophagus (SCCE) is a highly aggressive disease characterized by early dissemination and poor prognosis. Because of the rarity of this disease, few previous studies have investigated the biomarkers associated with its prognosis. Leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5) is a stem cell marker and a member of the canonical Wnt-signaling cascade. However, the clinical role of Lgr5 in SCCE remains unknown.
  
  
  METHODS
  Tissue sections were obtained from 44 patients diagnosed with SCCE and expression of Lgr5 was examined by immunohistochemistry. The correlations between Lgr5 expression, and clinical parameters and prognostic significance were evaluated.
  
  
  RESULTS
  Lgr5 was expressed in SCCE cancer tissues. High Lgr5 expression was significantly correlated with lymph node metastasis (p = 0.003), late stage (p = 0.003) and unfavorable response to chemotherapy (p = 0.013) according to RECIST 1.0 criteria. Patients with higher Lgr5 expression levels had shorter overall survival times than those with lower expression levels.
  
  
  CONCLUSIONS
  These results demonstrated that overexpression of Lgr5 was significantly correlated with lymph node metastasis, tumor stage, and response to chemotherapy. Furthermore, high levels of Lgr5 expression appeared to be associated with poorer survival in patients with SCCE.
authors.forename: Wei-Wei
authors.initials: WW
authors.lastname: Chen
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
authors.forename: Dong-Sheng
authors.initials: DS
authors.lastname: Zhang
authors.forename: Hui-Yan
authors.initials: HY
authors.lastname: Luo
authors.forename: Zhi-Qiang
authors.initials: ZQ
authors.lastname: Wang
authors.forename: Feng-Hua
authors.initials: FH
authors.lastname: Wang
authors.forename: Miao-Zhen
authors.initials: MZ
authors.lastname: Qiu
authors.forename: Chao
authors.initials: C
authors.lastname: Ren
authors.forename: Xiao-Li
authors.initials: XL
authors.lastname: Wei
authors.forename: Wen-Jing
authors.initials: WJ
authors.lastname: Wu
authors.forename: Yu-Hong
authors.initials: YH
authors.lastname: Li
authors.affiliation: Department of Medical Oncology, Sun Yat-sen University Cancer Center, 651 Dong Feng Road East, Guangzhou 510060, China. xurh@sysucc.org.cn.
authors.forename: Rui-Hua
authors.initials: RH
authors.lastname: Xu
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism; D018288:Carcinoma, Small Cell / Q000235:genetics / Q000473:pathology* / Q000628:therapy; D018450:Disease Progression; D004358:Drug Therapy; D004938:Esophageal Neoplasms / Q000235:genetics / Q000473:pathology*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008207:Lymphatic Metastasis / Q000276:immunology / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; C116884:LGR5 protein, human; D043562:Receptors, G-Protein-Coupled