NSCLC driver mutations in the Quebec population: Epidemiologic and clinical evaluation.

Abstract

e22159 Background: Recent advances in lung cancer treatment embrace the recognition of molecular pathways implicated in its pathogenicity, paving the path to personalized therapies. We conducted a retrospective analysis to characterize the molecular features of the population treated for non-squamous non-small cell lung cancer (NS-NSCLC) in the province of Quebec. Methods: 622 patients with NS-NSCLC and adequate tumor blocks, treated at the CHUM between 2006 and 2008, were included. All samples were tested for ALK translocations (by IHC and FISH), EGFR classical exon 19 and 21 mutations by PCR (fragment analysis and qPCR) and for KRAS codon 12 and 13 mutations by mismatch PCR-RFLP. Molecular features were matched to demographic characteristics and clinical outcomes. Results: So far, complete results are available for 153 patients. Considering the amount of tumor tissue available, this population is largely represented by patients with local or loco-regional disease (n= 140, 91.5%). A minority of patients (10.3%) was never or light smokers (< 10 pack-yrs). Only 2 patients (1.3%) were of Asian descent. The following table depicts the outcomes of this cohort of patients segregated according to mutation status and extent of disease. Conclusions: ALK rearrangements were not identified in this unselected NS-NSCLC population characterized by localized disease and strong smoking history. ALK translocation prevalence in different populations is likely to be largely influenced by its tumor stage distribution, tobacco exposure and the use of selection criteria for molecular testing. An expanded cohort of patients will be presented at the meeting. [Table: see text]