evaluation of the total oxidant status to the antioxidant capacity ratio as a valuable biomarker in breast cancer patients

Background: the oxidative balance is a state of equilibrium between oxidants and antioxidants disrupted in various disorders, including bc. this study aimed to assess this equilibrium in breast cancer (bc) patients by looking at the oxidant-to-antioxidant ratio.methods: this case-control study comprised 40 women patients with breast cancer and 30 age-matched healthy individuals. the oxidation-reduction colorimetric technique was used to determine serum levels of total oxidant status (tos) and total antioxidant capacity (tac). the oxidant-to-antioxidant balance was estimated using the tos- to- tac ratio (tos/tac).results: the mean tos in healthy individuals was 8.40±2.06 µmol/l, while in bc patients it was 13.31±2.16 µmol/l (p< 0.001). the mean serum level of tac was 1.43±0.21 mmol/l in healthy individuals and 1.19±0.15 mmol/l in bc patients (p< 0.001). the mean serum tos/tac was 6.01±0.32 in the healthy individuals and 11.42±0.41 in the bc patients (p< 0.0001). there were direct correlations between tac and estrogen receptor (r=0.339, p=0.038). the tos/tac level has a sensitivity of 100% and specificity of 83.33%, distinguishing patients with bc from healthy controls (p< 0.001). a significant trend of increasing risk with rising tos/tac levels was also seen [or=3.62, (95 % ci 1.79, 7.35)].conclusions: in breast cancer, the serum tos to tac ratio can better diagnose oxidative equilibrium than either component alone.