Impact of smoking on metabolic changes and effectiveness of drugs used for lung cancer.

Abstract

This article reviews the published studies dealing with the influence of cigarette smoking on metabolic changes and effectiveness of drugs used in the systemic chemotherapy of the lung cancer. The literature search of interactions between cigarette smoking and drugs used for lung cancer was carried out. The abstracted data mostly involved some induction of key drug-metabolizing enzymes of cytochrome CYP1A1/2, CYP2D6, CYP3A4 and isoforms of UDP-glucuronosyltransferase. Metabolic changes are important both in the non-chemotherapy and for the drugs used in the chemotherapy. They can change pharmacokinetic and pharmacodynamic effects of drugs. Primarily, we addressed potential differences in drug effects on smokers and non-smokers. The increased clearance of erlotinib and irinotecan may have impact on effectiveness of the lung cancer therapy. The effects of taxanes and gemcitabine are more complex. The evaluated studies show that continued smoking after lung cancer diagnosis is related to poor prognosis, reduced survival, risk of second primary malignancies, and increased cancer recurrence. Of particular importance is the deterioration in the quality of life and an increased incidence of the adverse drug reactions in smokers. The patient's cigarette smoking history should be considered carefully and smoking cessation must be taken into account.