title: Epidermal growth factor receptor as a predictor of tumor response to preoperative chemoradiation in locally advanced gastric carcinoma.
abstract: OBJECTIVE
  The purpose of our study was a retrospective evaluation whether the intensity of epidermal growth factor receptor (EGFR) expression predicts tumor response to preoperative chemoradiotherapy in patients with locally advanced gastric carcinoma.
  
  
  METHODS
  Thirty-six patients with gastric adenocarcinoma (cT2-4 or N+) were studied. Preoperative treatment consisted of 30-45 Gy of gastric irradiation with continuous 5-fluorouracil and weekly cisplatin. Surgical resection was performed 4-6 weeks later. EGFR expression in pretreatment tumor biopsies was assessed by immunohistochemistry. Level of EGFR expression was determined from the intensity and extent of staining. Tumor response was defined as a reduction of at least one T-stage level and/or finding of intense tumor regression in histopathologic examination.
  
  
  RESULTS
  Seventeen patients responded to preoperative chemoradiation -- 8 patients (22%) had pathologic complete response, 9 patients (25%) were downstaged. Positive EGFR expression was found in 8 tumors (22%), and represented a significant predictive marker of poor tumor response in multivariate logistic regression analysis (p = 0.015). Response to chemoradiotherapy was found in 60% (16/28) of EGFR negative patients and in 13% (1/8) of EGFR positive patients (p = 0.044). None of the eight EGFR positive patients achieved pathologic complete response in comparison with 8/28 (29%) of patients with EGFR negative staining (p = 0.16).
  
  
  CONCLUSIONS
  EGFR may represent a molecular marker predictive for poor response to preoperative chemoradiotherapy in locally advanced gastric carcinoma.
authors.affiliation: Department of Oncology & Radiotherapy, Charles University Medical School & University Hospital, Hradec Kralove, Czech Republic. sirak@fnhk.cz
authors.forename: Igor
authors.initials: I
authors.lastname: Sirak
authors.forename: Jiri
authors.initials: J
authors.lastname: Petera
authors.forename: Jana
authors.initials: J
authors.lastname: Hatlova
authors.forename: Milan
authors.initials: M
authors.lastname: Vosmik
authors.forename: Bohuslav
authors.initials: B
authors.lastname: Melichar
authors.forename: Josef
authors.initials: J
authors.lastname: Dvorak
authors.forename: Zdenek
authors.initials: Z
authors.lastname: Zoul
authors.forename: Vera
authors.initials: V
authors.lastname: Tycova
authors.forename: Michal
authors.initials: M
authors.lastname: Lesko
authors.forename: Marian
authors.initials: M
authors.lastname: Hajduch
mesh_terms: D000230:Adenocarcinoma / Q000532:radiotherapy* / Q000601:surgery; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D002945:Cisplatin / Q000627:therapeutic use; D003131:Combined Modality Therapy; D066246:ErbB Receptors / Q000378:metabolism*; D005472:Fluorouracil / Q000627:therapeutic use; D005743:Gastrectomy; D006801:Humans; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D011300:Preoperative Care; D011879:Radiotherapy Dosage; D013274:Stomach Neoplasms / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D016896:Treatment Outcome
chemical_list: D066246:ErbB Receptors; D002945:Cisplatin; D005472:Fluorouracil