title: Prognostic significance and frequency of EGFR expression and amplification in surgically resected advanced gastric cancer.
abstract: OBJECTIVE
  The aim of this study is to find the frequency and the role of epidermal growth factor receptor expression as a prognostic biomarker in gastric cancer.
  
  
  METHODS
  We evaluated the prognostic value and frequency of epidermal growth factor receptor expression and amplification using immunohistochemistry and silver in situ hybridization in a large cohort of curatively resected gastric cancer.
  
  
  RESULTS
  Of the total of 935 cases, 294 (31.4%), 101 (10.8%) and 36 (3.9%) patients showed epidermal growth factor receptor 1+, 2+ and 3+ expression on immunohistochemistry, respectively. Epidermal growth factor receptor-positive (2+/3+) patients more frequently had intestinal type than epidermal growth factor receptor-negative (0/1+) patients (82.5 vs. 44.1%, P < 0.001). After adjusting for sex, age, stage and adjuvant chemotherapy, epidermal growth factor receptor-positive patients had a favorable overall survival outcome compared with epidermal growth factor receptor-negative patients (hazard ratio, 0.734; 95% confidence interval, 0.541-0.997; P = 0.047), especially in Stage III disease (hazard ratio, 0.676; 95% confidence interval, 0.472-0.968; P = 0.033). Among the 393 cases available for  in situ hybridization, the correlation between immunohistochemistry and in situ hybridization was statistically significant (P = 0.001). Thirteen patients with gene amplification (3.3%) did not show different survival outcome with others (P = 0.359).
  
  
  CONCLUSIONS
  Epidermal growth factor receptor positivity was an independent favorable prognostic factor for gastric cancer, especially in Stage III disease.
authors.affiliation: Division of Medical Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul Department of Internal Medicine, Yonsei University College of Medicine, Seoul.
authors.forename: Ji Soo
authors.initials: JS
authors.lastname: Park
authors.affiliation: Division of Medical Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul Department of Internal Medicine, Yonsei University College of Medicine, Seoul.
authors.forename: Hyo Song
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Department of Pathology, Yonsei University College of Medicine, Seoul.
authors.forename: Yoon Sung
authors.initials: YS
authors.lastname: Bae
authors.affiliation: Department of Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Jae-Ho
authors.initials: JH
authors.lastname: Cheong
authors.affiliation: Division of Medical Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul Department of Internal Medicine, Yonsei University College of Medicine, Seoul.
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Rha
authors.affiliation: Department of Surgery, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Sung Hoon
authors.initials: SH
authors.lastname: Noh
authors.affiliation: Department of Pathology, Yonsei University College of Medicine, Seoul kimhyunki@yuhs.ac.
authors.forename: Hyunki
authors.initials: H
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D017024:Chemotherapy, Adjuvant; D002945:Cisplatin / Q000627:therapeutic use; D018572:Disease-Free Survival; D004317:Doxorubicin / Q000627:therapeutic use; D004359:Drug Therapy, Combination; D005260:Female; D005472:Fluorouracil / Q000627:therapeutic use; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D012189:Retrospective Studies; D012834:Silver / Q000737:chemistry; D013274:Stomach Neoplasms / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology; D015996:Survival Rate
chemical_list: D014408:Biomarkers, Tumor; D002945:Cisplatin; D004317:Doxorubicin; D005472:Fluorouracil; D018719:Erb-b2 Receptor Tyrosine Kinases; D012834:Silver
keywords: biological markers; receptor, epidermal growth factor; rognosis; stomach neoplasms