title: EGFR mutation status in primary lung adenocarcinomas and corresponding metastatic lesions: discordance in pleural metastases.
abstract: We evaluated EGFR and KRAS mutations between 37 paired primary tumors and corresponding metastases in lung adenocarcinoma. A substantial discordance was found in EGFR mutation status between primary tumors and corresponding metastases including pleural metastases. Moreover, the responsiveness to EGFR tyrosine kinase inhibitors tend to be correlated with EGFR mutation status in metastatic lesions than in primary tumors.
  
  
  BACKGROUND
  The aim of this study was to compare epidermal growth factor receptor (EGFR) and KRAS mutations between primary tumors and corresponding metastases including pleural metastases in lung adenocarcinoma.
  
  
  METHODS
  Thirty-seven paired primary lung adenocarcinomas and corresponding metastatic tumors were analyzed for EGFR and KRAS mutations. In addition, 21 pleural metastases including malignant pleural effusion or pleural biopsy were used in performing these mutation analyses.
  
  
  RESULTS
  EGFR mutations were detected in 18 primary lung adenocarcinomas (48.6%) and in 16 corresponding metastases (43.2%). EGFR mutations showed a discordance rate of 16.2% (6 of 37 patients) between primary lung adenocarcinomas and corresponding metastases. Among 21 pleural metastases, 3 patients (14.3%) showed that the EGFR mutation was discordant. KRAS mutations were detected in one primary tumor and in two metastatic tumors. Eighteen patients were treated with EGFR tyrosine kinase inhibitors. One of seven patients who experienced partial response had EGFR mutations only in the metastasis, and two of seven patients who experienced progressive disease carried wild-type EGFR only in the metastasis.
  
  
  CONCLUSIONS
  EGFR mutations were discordant between primary tumors and corresponding metastases in a significant portion of lung adenocarcinomas. Furthermore, these discordance was also observed in metastases to the pleura, the nearest metastatic site.
authors: Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, Korea.
authors: Hye-Suk
authors: HS
authors: Han
authors: Dae-Woon
authors: DW
authors: Eom
authors: Joo Heon
authors: JH
authors: Kim
authors: Kyung-Hee
authors: KH
authors: Kim
authors: Hyang-Mi
authors: HM
authors: Shin
authors: Jin Young
authors: JY
authors: An
authors: Ki Man
authors: KM
authors: Lee
authors: Kang Hyeon
authors: KH
authors: Choe
authors: Ki Hyeong
authors: KH
authors: Lee
authors: Seung Taik
authors: ST
authors: Kim
authors: Ji Hae
authors: JH
authors: Koo
authors: Ho-chang
authors: HC
authors: Lee
authors: Ok-Jun
authors: OJ
authors: Lee
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology; D000310:Adrenal Gland Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000556:secondary; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000235:genetics*; D001859:Bone Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000556:secondary; D001932:Brain Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000556:secondary; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy / Q000235:genetics* / Q000556:secondary; D004273:DNA, Neoplasm / Q000235:genetics; D066246:ErbB Receptors / Q000235:genetics*; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000556:secondary; D008175:Lung Neoplasms / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D009367:Neoplasm Staging; D010997:Pleural Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000556:secondary; D016133:Polymerase Chain Reaction; D011379:Prognosis; D011518:Proto-Oncogene Proteins / Q000235:genetics; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins / Q000235:genetics
chemical_list: D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; C512478:EGFR protein, human; D066246:ErbB Receptors; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins