title: [Detection of EGFR and K-ras mutations in non-small cell lung cancer using cytological specimens].
abstract: OBJECTIVE
  To validate the feasibility for detecting EGFR and k-ras mutations using cytological specimens.
  
  
  METHODS
  Cytological specimens including fine-needle aspiration (FNA), pleural effusion (PLE) and fiberoptic bronchoscopic (FOB) brushing were collected from patients with non-small cell lung cancer (NSCLC ) from January 2011 to July 2011 at the Department of Cytology, Cancer Hospital, Chinese Academy of Medical Sciences (CHCAMS). Polymerase chain reaction (PCR) was carried out to amplify EGFR exons 18-21 and k-ras codons 12-13, and then the PCR products sequencing and analysis were performed.
  
  
  RESULTS
  Fifty cytological specimens were collected including 19 cases of FOB, 9 cases of FNA, 22 cases of PLE. Of them DNA was successfully extracted in 43 cases, and specific PCR amplification products sequencing were performed in 42 cases. EGFR mutations were detected in 14 of 42 specimens (33.3%), the frequencies of EGFR mutations in exons 19, 20 and 21 were 16.7% (7/42), 4.8% (2/42) and 11.9% (5/42), respectively, and no mutation was found in exon 18. Higher frequencies of EGFR mutations were detected in exons 19 and 21 (85.7%). Mutations were identified in 38.7% (12/31) cases of adenocarcinoma. K-ras mutations were found in 2 of 42 specimens (4.8%). EGFR and K-ras mutations were not found in the same case.
  
  
  CONCLUSIONS
  Cytological specimens are feasible for detecting EGFR and K-ras mutation. This is especially beneficial in patients in whom histological materials can not be obtained.
authors: Department of Pathology, Cancer Hospital (Institute), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China.
authors: Shan-shan
authors: SS
authors: Lu
authors: Xin
authors: X
authors: Xu
authors: Hui-qin
authors: HQ
authors: Guo
authors: Jian
authors: J
authors: Cao
authors: Qin-jing
authors: QJ
authors: Pan
authors: Ming-rong
authors: MR
authors: Wang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044963:Biopsy, Fine-Needle; D001999:Bronchoscopy; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000473:pathology; D003062:Codon; D066246:ErbB Receptors / Q000235:genetics*; D005091:Exons; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009154:Mutation; D059645:Mutation Rate; D010996:Pleural Effusion / Q000473:pathology; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D012737:Sex Factors; D012907:Smoking; D055815:Young Adult; D018631:ras Proteins / Q000235:genetics*
chemical_list: D003062:Codon; C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; C512478:EGFR protein, human; D066246:ErbB Receptors; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins