Erlotinib-Associated Rash in Advanced Non-Small Cell Lung Cancer: Relation to Clinicopathological Characteristics, Treatment Response, and Survival.

Systematic treatment of advanced non-small cell lung cancer (NSCLC) includes targeted treatment with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). The development of skin rash and its intensity have been associated with EGFR TKI's efficacy. The main purpose of this study was to further investigate the potential value of erlotinib-associated rash as a predictor of prognosis and treatment response in a real-world cohort of patients with advanced NSCLC. The medical records of all NSCLC patients treated with erlotinib at the Oncology Unit of GPP, Sotiria Athens General Hospital between January 1, 2014 and August 31, 2016 were retrospectively reviewed. Seventy-nine patient medical records fulfilled the criteria and were included in the study. Development of erlotinib-associated rash was correlated with clinicopathological characteristics of patients, treatment response, and overall survival (OS) using univariate and multivariate Cox regression analysis. The number of patients with rash was greater in the responders group (90% vs. 46.4%, p = 0.015). In univariate analysis, there was a statistically significant association between rash development and time to progression (TTP) [HR: 0.32 (0.17-0.57), p < 0.001]. With multivariate Cox regression analysis, it was found that PS ≥ 2 (HR: 2.01, 95% CI: 1.12-3.60, p = 0.018) and rash (HR: 0.34, 95% CI: 0.18-0.63, p = 0.001) were independently associated with TTP and also that the duration of treatment with erlotinib (HR: 0.58, 95% CI: 0.42-0.80, p = 0.001) and rash (HR: 0.10, 95% CI: 0.20-0.48, p = 0.004) was an independent predictor of survival. Our results suggest that erlotinib-associated rash may represent a clinically valuable biomarker for the prediction of treatment response and OS in patients with advanced NSCLC.