Molecular biology of advanced NSCLC and survival: seeking the best therapy

Background: Molecular biology in advanced non-small cell lung cancer (NSCLC) is currently an essential tool for ensuring the best therapy to our patients, even at a small hospital. Methods: Retrospective study of NSCLC patients with molecular diagnostic followed in pulmonary oncology consultation in a Portuguese University Hospital, with diagnoses made between January 2012 and December 2018, and follow-up until June 2018. Results: Of the 79 patients included, 74.7% were males, with a mean age of 65.7±9.5 years. Smoking and former smoking habits were present in 35.5% each. The majority of patients (90.7%) had an ECOG PS between 0 and 2 and half evidenced a substantial weight loss. At presentation, 77.2% of patients were at stage IV. In 79.2% of cases with actionable driver mutations, mainly EGFR mutations and ALK translocations, tyrosine kinase inhibitors (TKI) were used. Liquid biopsy allowed identification of T790M mutation in 4 patients with progression under TKI. Classic chemotherapy was also used in 92.4% of cases and immunotherapy with Pembrolizumab in 5 patients. Mean overall survival (OS) was 17.6 months, with mean progression free survival (PFS) of 11.2 months. In the stage IV group, both OS and PFS were higher in patients who underwent targeted therapy compared to those who did not (24.4±5 vs 18±4.4 months, p=0.003; 15.2±2.4 vs 10.6±1.8 months, p=0.009). Conclusions: In our hospital, molecular diagnostic is performed in all patients with advanced NSCLC to customize therapy. This study, while showing our local experience, corroborates data obtained in the literature. Thus, despite the small sample size, this may be the basis for future studies and help improve clinical practice.