Impact of EGFR Mutation on Prognosis of Stage IV Non-Squamous Non-Small Cell Lung Cancer NSCLC: A Retrospective Analysis

Abstract

Background: Patients with activating somatic mutations in the Epidermal Growth Factor Receptor (EGFR) have better prognosis when treated with Tyrosine Kinase Inhibitors (TKI) as the standard treatment of care in this group of patients.Aim of the work: To study the impact of EGFR mutation on prognosis of advanced stage non-squamous NSCLC.Patients and Methods: This is a cross-sectional, retrospective- cohort study of stage IV non squamous non-small cell lung cancer (January 2019- june2021). This study was done at both Clinical Oncology and Nuclear Medicine department Ain Shams university Hospital and Nasser Institute Cancer Centre for research and treatment (NICC)Primary end point: progression free survival .Secondary end point: overall survival, and response rate to treatment. Results: From the 87 patients which performed screening for EGFR mutations, 20 (23%) had mutations, while 64 (73%) had wild type EGFR. The median progression free survival of patients with EGFR mutation received Gefitinib as standard treatment were better than progression free survival of wild type patients treated with standard chemotherapy (11.0 vs 6.0 months, respectively; P = 0.016). Overall survival also improved in the population with EGFR mutation treated with Gefitinib as standard treatment than those with wild type treated with standard chemotherapy (24.0 months vs 11.0 months respectively; P = 0.014).Conclusion: These data contribute for a better prognosis of stage IV lung cancer population harboring EGFR mutation, confirming a better progression free survival, overall survival and response rate for those patients with EGFR TKI as standard treatment.