title: Quantification of EGFR mutations in primary and metastatic tumors in non-small cell lung cancer.
abstract: BACKGROUND
  EGFR mutation detection has been widely applied in the prediction of TKIs therapy in Non-Small Cell Lung Cancer (NSCLC). Metastatic tumors rather than primary tumors were usually assayed for those patients in advanced stages. Although the difference of EGFR mutation status in primary and metastatic tumors has been reported, the quantitative difference (ratio of mutated EGFR among total EGFR) in primary and metastatic tumors as well as in different sites of primary tumors was not clear.
  
  
  METHODS
  Genomic DNA in Formalin Fixed-Paraffin Embedded samples of primary and metastatic tumors of 50 NSCLC patients was extracted. Real-time fluorescent PCR was performed to quantify the EGFR mutation ratios.
  
  
  RESULTS
  The EGFR mutation ratios detected in different sites of primary tumors were highly concordant, whereas the EGFR mutation ratios in metastatic tumors were lower than those in primary tumors.
  
  
  CONCLUSIONS
  Randomly chosen sample may reliably represent the type and ratio of mutations of EGFR in primary tumors. EGFR mutation ratios in primary tumors and metastatic tumors are different. If metastatic tumors are used for the detection of EGFR mutation, the sensitivity of the detection assay must be considered.
authors.forename: Bing
authors.initials: B
authors.lastname: Wei
authors.forename: Ke
authors.initials: K
authors.lastname: Yang
authors.forename: Jiuzhou
authors.initials: J
authors.lastname: Zhao
authors.forename: Yuxi
authors.initials: Y
authors.lastname: Chang
authors.forename: Zihui
authors.initials: Z
authors.lastname: Ma
authors.forename: Bing
authors.initials: B
authors.lastname: Dong
authors.forename: Yongjun
authors.initials: Y
authors.lastname: Guo
authors.affiliation: Department of Pathology, Henan Cancer Hospital, the Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou 450008, Henan, China. majie@medmail.com.cn.
authors.forename: Jie
authors.initials: J
authors.lastname: Ma
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000556:secondary; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000556:secondary; D004252:DNA Mutational Analysis; D066246:ErbB Receptors / Q000235:genetics*; D005260:Female; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies
chemical_list: C512478:EGFR protein, human; D066246:ErbB Receptors