Status of Oxidative Stress and Antioxidant Levels in Smokers with Breast Cancer from Western Nepal

Background: Research indicates that oxidative stress induced by smoking plays a role in breast cancer. In view of these reports, we aimed to study th relationship between smoking and oxidative stress in breast cancer patients from the western region of Nepal. Materials and Methods: The study included a control group of 42 females (non-smoking healthy women) and a test group sudivided into Group I consisting of 46 female breast cancer patients who were smokers and Group II consisting of 42 non-smoking breast cancer patients. Detailed history of the patients was collected with the help of pre-test proforma. Plasma levels of malondialdehyde (MDA), total antioxidant activity (TAA) which represents total dietary antioxidants, vitamin C and ${\alpha}$- tocopherol were estimated by standard methods. Statistical analysis was done using SPSS version 16. Results: The plasma MDA, TAA, vitamin C and ${\alpha}$- tocopherol were $1{\pm}1.4nmol/ml$, $918{\pm}207{\mu}mol/L$, $1{\pm}0.24mg/dL$ and $0.94{\pm}0.31mg/dL$ in controls, $5{\pm}1.2nmol/ml$, $458{\pm}166{\mu}mol/L$, $0.64{\pm}0.32mg/dL$ and $0.5{\pm}0.3mg/dL$ in Group-I and $2.56{\pm}1.2nmol/ml$, $663{\pm}178{\mu}mol/L$, $0.78{\pm}0.2mg/dL$ and $0.77{\pm}0.2mg/dL$ in Group- II, respectively. Vitamin C, ${\alpha}$- tocopherol and TAA (p=0.001) were significantly reduced whereas MDA (p=0.001) was significantly raised in Group-I when compared to controls and Group-II. Conclusions: We observed a significant rise in oxidative stress and low levels of antioxidants in breast cancer patients with smoking habit. It is well known that free radicals facilitate the progression of breast cancer, possibly increasing the risk of progression to the next stage.