Purpose: Although many studies have confirmed the synergic effects of combining chemotherapy (CT) and radiotherapy (RT), clinical data evaluating safety and efficacy of erlotinib in combination with RT in locally advanced non-small-cell lung cancer (NSCLC) are limited. The aim of this study was to determine the feasibility, tolerability, and efficacy of the concurrent addition of erlotinib to the standard three-dimensional conformal thoracic RT in patients with unresectable or locally advanced NSCLC who are not candidates for receiving standard CT.
Patients and methods: Feasibility and tolerability, assessed by evaluating adverse events (AEs), and effectiveness, by calculating progression-free survival (PFS), overall survival (OS), cancer-specific survival (CSS), and objective response rate (ORR), were analyzed in 30 patients receiving RT alone and 60 receiving RT and erlotinib.
Results: Erlotinib with RT showed an extended CSS and a higher rate of complete responses compared with RT alone. No differences between groups were found regarding OS, PFS, and ORR. AEs were significantly higher in the combined treatment, which mainly included cutaneous toxicity, dyspnea, fatigue, hyporexia, diarrhea, and infection. Erlotinib did not increase the toxicity produced by RT.
Conclusion: The combination of erlotinib with RT produced, in our study, a scarce clinical benefit in the treatment of unresectable or locally advanced NSCLC, limited to complete responses and longer CSS rate compared with RT alone. Increased toxicity events were associated with combined therapy, which mainly included cutaneous toxicity. In our opinion, further studies in molecularly unselected lung cancer patients treated with EGFR TKIs and RT are not indicated. The use of biomarkers for the identification of patients that are most likely to benefit from this treatment is an essential next step in the research of this condition.
Keywords: concurrent; erlotinib; non-small-cell lung cancer; radiotherapy.