Survival and prognostic factors in non-small cell lung cancer patients with mutation of the EGFR gene treated with tyrosine kinase inhibitors in a peruvian hospital

The identification of the epidermal growth factor mutation (EGFR) is a positive prognostic factor for survival and therapeutic response to tyrosine kinase inhibitors (TKIs) in patients with non-small cell lung cancer (NSCLC). TKIs are considered first line treatment in Patients with stages IIIB and IV NSCLC. We investigated the survival and prognostic factors in NSCLC patients with the mutation of the EGFR in routine clinical practice. We conducted a retrospective cohort observational study of 72 patients with non-small cell lung cancer (NSCLC) with EGFR gene mutations that received treatment with erlotinib from January 2009 to December 2015. Kaplan-Meier curves were presented. The association between independent variables and survival was analyzed using the Long-Rank test in bivariate analysis and for multivariate analysis, Cox proportional hazards method was used to calculate hazard ratios (HRs) and corresponding 95% confidence intervals (CIs). We included data from 72 patients, which were followed for a total of 1144 patient-months. The majority of patients were female (61.11%), non-smokers (62.50%), and with histological type corresponding to adenocarcinoma (76.38%). The most frequent EGFR gene mutation was the deletion of exon 19 (65.27%). The majority of patients presented with comorbidities (77.78%), most commonly hypertension. Almost all patients had stage IV NSCLC. Out of the 72 cases, 65 (90.28%) died. The median survival was 9.3 months (95% CI, 7.01-16.93). When comparing the survival curves when using the Log Rank Test, histological type (P = 0.01), place of mutation (P = 0.06), hemoglobin (P = 0.01) and age (P = 0.01) were significant associated to overall survival (OS). In multivariate analysis, only age (HR, 1.02; 95% CI, 1-1.04, P = 0.009) and hemoglobin (HR, 0.70; 95% CI, 0.55-0.89, P = 0.003) remained significant. In conclusion, the median OS of NSCLC patients with positive EGFR gene mutation treated with TKI was 9.3 months. Bivariate and multivariate analysis showed that younger age and a higher hemoglobin level were the most important factors associated with survival.