Non-small cell lung cancer in Brazilian non-smokers and light-smokers: epidemiological, genotypic and clinical characteristics

The incidence of lung cancer in non-smokers and light smokers has increased worldwide. In Brazil, data regarding the epidemiology, risk factors, and molecular assessment of this subpopulation are scarce. Here, we present the results of a single-center prospective cohort study on patients with non-small-cell lung cancer (NSCLC) in non-smokers or light smokers, the objective of which was to clinically and epidemiologically characterize the sample. Materials and Methods: We consecutively and prospectively recruited patients with non-smoking NSCLC or light smokers. Epidemiological data such as passive smoking, exposure to indoor pollutants, history of cancer, and other data of interest were obtained through questionnaires during personal interviews, and the performance status was evaluated via the use of ECOG (Eastern Cooperative Oncology Group) information. Histopathological and molecular characteristics were also collected. Results: In this study, 120 patients were recruited, 75 patients were female (62%), and the median age was 63 years (30–94 years). Of the total cohort, 109 were non-smokers, and 59 were Caucasian. Exposure to pollutants or indoor smoking was reported in 83 patients. Adenocarcinoma was the most frequent histology (90%), and epidermal growth factor receptor (EGFR)-activating mutation was the main genomic alteration detected among those analyzed (44%). ECOG—Performance Status 1 was the most frequently reported performance status (48%). None of these variables were associated with the prognosis. Conclusions: In this cohort, enriched with female and Caucasian patients, adenocarcinoma was the most frequent histology, and EGFR mutation was the most common genomic alteration.