RESUMEN
OBJECTIVES: Determine the frequency of actionable mutations in non-small cell lung cancer (NSCLC) and their correlation with overall survival (OS) and the site of metastases. METHODS: We performed a descriptive cross-sectional study at the Hospital de Especialidades Eugenio Espejo, Ecuador, between 2017 and 2020. Demographic, pathological, and molecular alterations in epidermal growth factor (EGFR), Anaplastic lymphoma kinase (ALK), ROS proto-oncogene 1 (ROS1), Programmed death-ligand 1 (PD-L1) expression, and clinical data detailed in patients' medical records with metastatic NSCLC were collected and analyzed. Seventy-nine stage IV patients had NSCLC; adenocarcinoma histology represents 56 (70.9%). The predominant mutation was in EGFR (22.8%); the most common variant was the deletion of exon 19 (72.2%). The most common metastatic site was in the contralateral lung (22.3%); however, this variable showed no significant correlation to the molecular markers (p=0.057). The overall survival (OS) and the status of molecular markers are not statistically significant (p=0.27). OS was better for non-mutated EGFR than for mutated EGFR (p=0.012). However, the frequency values are unrelated to contralateral lung metastasis or survival. CONCLUSIONS: Our frequency mutations are concordant with those found in other studies in Latin America. EGFR was the most common biomarker mutation, and there was a better OS in EGFR non-mutated patient.