Clinical perspective on PROSE: does VeriStrat testing improve selection of second-line treatment for patients with non-small cell lung cancer?

Erlotinib is an active agent that triggers dramatic and sustained responses in a subset of patients with non-small cell lung cancer (NSCLC). The vast majority of these patients with miraculous erlotinib responses harbor deletion 19 or L858R activating mutations in the epidermal growth factor receptor (EGFR) gene (1). However, erlotinib was designed to inhibit the wild-type version of the EGFR gene and does have activity for treating EGFR wild-type cancers. The question of whether or not to use erlotinib for EGFR wild-type cancers and in what line of treatment is a matter of ongoing debate. The PROSE investigators have added fuel to the fire of this debate with their recent publication.