Clinical surrogate markers of survival in advanced non-small cell lung cancer (NSCLC) patients treated with second–third line erlotinib

Background Inhibition of the EGFR pathway is a useful strategy in the treatment of patients with advanced NSCLC. The aim of this study is to assess predictive clinical parameters of efficacy. Methods and patients Sixty-two patients with advanced NSCLC were treated with erlotinib as second–third line (150mg/day). Baseline patient characteristics were: performance status (PS) 1: 92%; median age, 58 years; males, 73%; adenocarcinoma, 45%; current/former smokers, 83%. During erlotinib treatment, 35% of patients had no rash, 32.3% had grade 1 rash, 26% had grade 2 rash and 6.5% patients developed grade 3 rash. Results For patients with grades 2–3 rash vs. those with grades 0–1 rash, time to tumor progression (TTP) and overall survival (OS) were 92 vs. 41 days (p=0.0381) and 244 vs. 131 days (p=0.011), respectively. For patients with non-smoking history and current/former smokers, TTP and OS were 136 vs. 42 days (p=0.0015) and 324 vs. 133 days (p=0.0242), respectively. In addition, rash grade and smoking history were found to have a highly significant impact on TTP and OS, according to the Cox model. Conclusions Grade ≥2 rash and non-smoking history are associated with improved TTP and OS in advanced NSCLC patients treated with erlotinib.