Lung cancer worldwide is the most common malignancy in men, whereas in women it ranks second. At the same time the lung cancer is the leading cause of cancerrelated death. Today, smoking is considered as the major cause of lung cancer. About 90% of lung cancers in men and 78 % of lung cancers in women may be associated with long-term smoking.A total of 173 patients with histologically confirmed NSCLC and SCLC were included in this prospective-retrospective study. In the study, all patients were divided into two groups: operable ( 117) and inoperable (56). To quantify the association of certain risk factors and the incidence of lung cancer, an odds ratio (OR) 95 % CI was calculated. To determine the level of significance, the value of p <0.05 was taken, and the value of p <0.01 was taken for high significance.The mean age of the group was 60.2 ± 8.7 years, with the youngest patient in the study group aged 31 and the oldest 75 years. There were 80 pensioners (46.25%) and 59 (34,1%) able-bodied patients in the structure of the socioeconomic status. In regard to smoking status, the majority were smokers. The period of smoking was over 20 years and longer; in regard to intensity of smoking they were divided into three groups: smokers with more than 20 years of smoking experience and more than one pack of cigarettes per day -49.13%, smokers with more than 20 years of smoking experience and one pack of cigarettes per day -5.78%, and smokers who smoke more than 20 years but not continuously -15.61%. Occupational exposure was present in 16.18% of the study population, while positive family history was present in 20.81% of patients. Regarding heredity, applying the Chi-square test, we have shown that heredity has a highly significant correlation with the type of cancer reported in both groups.The demographic characteristics of the test are shown to be statistically significant in relation to lung cancer.