Epidermal growth factor receptor mutation in small cell lung cancer patients detected by mutant-enriched liquidchip technology from plasma in China.

Abstract

e17512 Background: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) has been widely used in non-small cell lung cancer (NSCLC), and the incidence of EGFR mutation in NSCLC is higher in China than in the United States and European countries. EGFR exons 19 and 21 mutation in NSCLC is related to response of tumors to EGFR TKIs, suggesting its usefulness as a biomarker. Some case studies reported that gefitinib-responsive small cell lung cancer (SCLC) with EGFR mutation. However, there are few large studies which reported the mutation status of SCLC patients. It is difficult to obtain tumor tissues to detect EGFR mutation in SCLC patients especially from surgery. This aim of the study is to know the EGFR mutation status in SCLC patients in China, and evaluate the feasibility of EGFR mutation detection from plasma by mutant-enriched liquidchip (MEL) technology. Methods: From September 2011 to January 2012, 27 cases of SCLC plasmas were collected at our Hospital, China. There are 6 female, 21 male. Age from 46 to 74 years old and median age is 60 years old. The stage (Veterans Administration Lung Study Group, VALSG): limited disease (LD) 6 cases, extensive disease (ED) 21 cases. Smoking history: non-smoker 8 cases, light smoker 0 cases, moderate smoker 3 cases and heavy smoker 16 cases. MEL technology was used to detect EGFR exon 19 and exon 21 mutations from plasma of 27 SCLC patients. Results: One of 27 cases was found with mutation in exon 19 of the EGFR gene. The patient with EGFR exon 19 mutation is a female and non-smoker. Conclusions: EGFR mutation is rare in SCLC patients, and may be more easily occurred in female and non-smokers. It is feasible to detect EGFR mutation for SCLC from plasma by MEL technology.