BELIEF (Bevacizumab and ErLotinib In EGFR Mut+ NSCLC)

Rationale: Advanced non-small-cell lung cancer (NSCLC) patients harbouring epidermal growth factor receptor (EGFR) mutations (del19 or L858R) show an impressive progression-free survival between 9 and 14 months when treated with erlotinib. However, the presence of EGFR mutations can only imperfectly predict outcome. The investigators hypothesize that progression-free survival could be influenced both by the pretreatment EGFR T790M mutation and by components of DNA repair pathways. The investigators propose a model of treatment whereby patients with EGFR mutations (single or with T790M) can attain a benefit with longer overall PFS when treated with erlotinib plus bevacizumab. When the patients are grouped by BRCA1 mRNA levels and T790M the hypothesis is that the combination of erlotinib plus bevacizumab can improve the PFS in all subgroups.