Assessment of EGFR mutations in patients diagnosed of squamous non-small cell lung cancer (NSCLC).

e18106 Background: Mutations in the Epidermal Growth Factor Receptor (EGFR) predict a better outcome to EGFR tyrosine kinase inhibitors than platinum-based chemotherapy in advanced non-small cell lung cancer (NSCLC). Previous studies with Caucasian patients have shown a prevalence of EGFR mutation of 10-15%. The aim of this study is to analyze the prevalence of EGFR mutations in squamous-cell NSCLC patients from an area of influence of 500,000 habitants. Methods: Prospective mutation testing in NSCLC patients included in our institution since October 2010 to January 2012 was performed on DNA obtained from available tumor tissue and cytologic samples, using ARMS-scorpion TheraScreen EGFR 29 Mutation Test Kit (Qiagen). Results: From 218 consecutive NSCLC diagnoses, 18 (8.25%) patients showed EGFR mutations: 6 (33.3%) exon 19 deletion, 9 (50%) exon 21 mutations (7 L858R and 2 L861Q) and 3 (16.6%) cases exon 20 insertion. In the EGFR mutated population, 16 (88.88%) patients were diagnosed as adenocarcinoma an...