Tobacco Smoking and Lung Cancer: Perception-changing facts

Abstract

Tobacco smoking remains the most established cause of lung carcinogenesis and other disease processes. Over the last 50 years, tobacco refinement and the introduction of filters have brought a change in histology, and now adenocarcinoma has become the most prevalent subtype. Over the last decade, smoking also has emerged as a strong prognostic and predictive patient characteristic along with other variables. This article briefly reviews scientific facts about tobacco, and the process and molecular pathways involved in lung carcinogenesis in smokers and never-smokers. The evidence from randomised trials about tobacco smoking's impact on lung cancer outcomes is also reviewed.

Keywords: Carcinogens; EML4 ALK fusion protein, human; K-Ras Gene; Lung Neoplasms; Nicotine; Receptor, Epidermal Growth Factor; Tobacco Smoking.

Figure 1:

Link between nicotine addiction and lung cancer via tobacco smoke carcinogens and carcinogenesis. Adapted from: Hecht SS. Tobacco smoke carcinogens and lung cancer. 7-MG, 06-MG = 7-methylguanine, 06-methylguanine; DNA = dioribonucleic acid; NER = nucleoside excision repair; BER = base excision repair.

Figure 2:

Relative risk of lung cancer, according to duration and intensity of smoking, men. Adapted from Cancer Research UK. Tobacco and cancer risk statistics.

Figure 3:

Impact of tobacco smoke on lung cancer. GA = general anaesthesia; Adenoca = adenocarcinoma; SCC = squamous-cell carcinoma; TKI = tyrosine kinase inhibitor; QoL = quality of life; CA = cancer; EGFR_MUT= epidermal growth factor mutation; K-Ras_MUT= Kirsten rat sarcoma viral oncogene homolog mutation; EML4 Alk = echinoderm microtubule-associated protein like 4-anaplastic lymphoma kinase fusion.