An association between cigarette smoking and lung cancer carcinogenesis is reviewed. It is highly possible, that "individual susceptibility" for tumor development exists and is related to polymorphic variants of genes encoding for enzymes, which are employed in metabolism of xenobiotic substances. The gathering of highly reactive molecules due to modified metabolic processes results in DNA adducts forming and increased tendency for mutations. Group of genes, responsible for proliferation, cell cycle arrest, apoptosis and DNA damage repair are frequently altered.