Breast cancer is one of the most common malignancy in women and is the leading cause of
cancer related death worldwide. Reactive oxygen species (ROS) play an important role in the development of
tumours. Several mechanisms leading to oxidative stress have been proposed in cancer patients. In this study
we aimed to measure and compare the levels of zinc, superoxide dismutase, catalase, vitamin C, vitamin E,
and malondialdehyde in breast cancer patients and age matched healthy controls. Methods: In this comparative
cross sectional study, 30 confirmed breast cancer cases and 30 age and sex matched controls were enrolled
after taking their consent. Blood sample was collected in EDTA vial, and the parameters of oxidative stress were
evaluated by spectrophotometric and atomic absorption spectrophotometric methods. Results: Zinc and MDA
level were significantly higher (p<0.001) in cases (106.4 µg/dl and 7.12 nmol/ml) compared to controls (89.8µg/
dl and 3.99nmol/ml). In contrast, there were lower catalase, vitamin C and E levels in cases (28.7±14.56,
0.92±0.35 and 0.68±0.13 mg/dl) compared to controls (37.1±14.7,1.62±0.59 and 1.02±0.22 mg/dl) and were
statistically significant (p<0.05 and p<0.001). Whereas, superoxide dismutase was lower in cases compared
to controls, but was not statistically significant. Conclusion: Zinc was found to be higher in our study as it
is a pivotal element in all rapidly growing tissues. Enhanced lipid peroxidation observed in the circulation of
breast cancer patients in our study can be attributed to over production of ROS and deficiency of antioxidant
defences. Oxidative stress in cancer cells may trigger excessive consumption of antioxidants as a compensatory
mechanism which lead to its lower concentration.