Efficacy was subsequently evaluated based on the determination of EGFR mutations and a subgroup study was carried out, finding that greater benefit was seen in non-smokers and patients with adenocarcinoma (with a greater probability of presenting an EGFR mutation), and that there was no benefit in terms of OS in those patients lacking an EGFR mutation [87]. The gene discussed is EGFR; the disease is adenocarcinoma.