Oxidative stress and chemotherapy-induced ovarian ablation in premenopausal women with breast cancer

The risk factors associated with breast cancer may exert their effects via generation of reactive oxygen species (ROS) which induces oxidative damage of DNA and neoplastic transformation. Estrogen has a role in the development and growth of Breast Cancer. In the present study we have evaluated the levels of serum malondialdehyde (MDA), estrogen, FSH and LH, vitamin E and vitamin C. All these parameters were estimated in 50 premenopausal breast cancer patients before and after chemotherapy and in 30 healthy controls. The results showed that estrogen and MDA levels were significantly increased in patients before therapy but the levels were significantly decreased following therapy (p < 0.001). The levels of FSH and LH which were found to be low in the patients before therapy, were elevated after therapy (p < 0.001). Antioxidants showed a decreased concentration in patients before therapy but their concentrations were significantly increased after chemotherapy (p < 0.001). We suggest that oxidative stress in premenopausal women with breast cancer may possibly result from a higher concentration of estrogen with corresponding low levels of antioxidants. Chemotherapy may be useful for premenopausal women with breast cancer because it causes premature menopause which ultimately prevents recurrence of disease. The evaluating parameters used in this study could be recommended for diagnostic and prognostic purposes in premenopausal breast cancer patients.