Clinical characteristics and survival in never smokers with lung cancer

INTRODUCTION AND OBJECTIVETo analyze the frequency, clinical characteristics and survival of patients with lung cancer (LC) who have never smoked in comparison to patients who smoke.PATIENTS AND METHODSA retrospective study in patients diagnosed with LC by cytohistology between 1999 and 2011. Survival was estimated by the Kaplan-Meier method. The χ(2) test was used to estimate the relationship between the variables.RESULTSA total of 2161 patients were diagnosed with LC, 396 (18.3%) of whom had never smoked. The mean age (±standard deviation) in this group was 72.85±10.52; 64.6% were women and 35.4% men. According to the cytohistology, 55.6% were adenocarcinoma, 20.5% squamous cell, 15% small cell, 2.7% large cell and 6.2% other subtypes. The diagnosis was made in advanced stage (iv) in 61.4%, and 14.4% of the patients received surgical treatment. Survival was 12.4%, with no differences between the two groups. In the group of never smokers, women had better survival than men.CONCLUSIONSOf the patients diagnosed with LC, 18.3% had never smoked. It was diagnosed mainly in women, at advanced stages and the most common histological type was adenocarcinoma. There were no survival differences compared to the group of smokers.