Epidermal Growth Factor Receptor Mutation in Small Cell Lung Cancer Patients Detected by Mutant-Enriched Liquidchip Technology from Plasma

ABSTRACT 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. Mutations of EGFR exons 19 and 21 in NSCLC is related to response of tumors to EGFR TKIs, suggesting their usefulness as biomarkers. Some case studies reported a 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 mutations in SCLC patients especially from surgery. The aim of this study was to determine 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. From September 2011 to March 2012, plasma from 35 cases of SCLC were collected at the Zhejiang Cancer Hospital, Hangzhou, China. There were 7 female, 28 male; age from 46 to 74 years old and median age of 60 years old. The stage (Veterans Administration Lung Study Group, VALSG): limited disease (LD) 8 cases, extensive disease (ED) 27 cases. Smoking history: non-smoker 10 cases, light smoker 0 cases, moderate smoker 3 cases and heavy smoker 22 cases. MEL technology was used to detect EGFR exon 19 and exon 21 mutations from plasma of 35 SCLC patients. One of 35 cases was found with mutation in exon 19 of the EGFR gene. The patient with EGFR exon 19 mutation was a female and non-smoker. EGFR mutation is rare in SCLC patients, and may more easily occur in females and non-smokers. It is feasible to detect EGFR mutation for SCLC from plasma by MEL technology. Disclosure All authors have declared no conflicts of interest.