[Detection of epidermal growth factor receptor gene mutations in advanced non-small cell lung cancer]

To investigate the mutations of epidermal growth factor receptor (EGFR) in tumor tissue and pleural effusion in advanced non-small cell lung cancer (NSCLC) patients, and to analyze the relationship between EGFR mutations and the clinicopathologic characteristics.

Two-hundred and forty-one cases of formalin-fixed, paraffin-embedded tumor tissues and 14 paired pleural effusions from advanced NSCLC patients were collected. Twenty-nine different EGFR mutations in exons 18-21 were assessed by scorpions and amplification refractory mutation system (scorpions ARMS) using real time PCR. The relationship between the EGFR mutations and clinical parameters was analyzed using statistical methods. EGFR mutation of 37 cases were detected with direct sequencing, and assessed the sensitivity, the specificity and the accuracy of scorpions ARMS.

EGFR somatic mutations were detected in 114 of 234 advanced NSCLC patients, with the mutation rate of 48.7%, including deletions in exon 19 in 65 patients and point mutation of L858R in exon 21 in 39 patients; both accounting for 91.2% (104/114) of all types of EGFR mutations. The test results of 14 paired pleural effusion specimens were entirely the same to the tissues. The concordance rate of 2 different detection methods was 94.6%. Mutation rate was higher in women (55.9%) than in men (42.2%), and there was no difference in mutation rates between smokers and non-smokers; patients in stage IIIB and stage IV; adenocarcinoma and non-adenocarcinoma.

EGFR somatic mutations appear to occur frequently in Chinese. Scorpions ARMS technology is a sensitive method to detect EGFR mutations and is suitable for screening patients who would likely respond to EGFR inhibitors therapy.