Clinical analysis of patients treated with afatinib for advanced non-small cell lung cancer: A Nagano Lung Cancer Research Group observational study.

Abstract

Afatinib has been available in Japan for the treatment of epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) since May 2014. We conducted an observational study in patients treated with afatinib in Nagano prefecture, focusing on response and associated toxicities. We analyzed the clinical records of NSCLC patients treated with afatinib between May 2014 and February 2015. The records of a total of 73 patients (27 men, 46 women) with a median age of 69 years (range: 42-85 years) were analyzed. Afatinib was administered to 11 patients as a first-line therapy, but it was predominantly administered as a fifth-line or beyond therapy (32 cases, 43.8%). The overall response rates for afatinib as a first-line therapy and beyond second-line therapy were 80% (95% confidence interval [CI]: 55.2-100.0%) and 27.1% (95% CI: 14.5-39.7%), respectively. The main toxicities grade >3 included diarrhea (8.2%), skin rash (6.8%), nausea (6.8%), and appetite loss (6.8%). A low body surface area (BSA) (<1.5m2) was significantly associated with a higher frequency of diarrhea grade >2, compared with a higher BSA (≥ 1.5m2). Forty-eight patients (63.0%) were treated without a dose reduction of afatinib. Although the survival benefit with afatinib remains unclear, our observational analysis demonstrated the feasibility of using afatinib for EGFR-mutated NSCLC in clinical practice. In particular, a relatively high level of drug delivery is possible. In addition, a lower BSA may be a predictor of diarrhea in patients treated with afatinib.