Background Short-term memory (STM) decline in breast cancer patients resulting from chemotherapy was evaluated by means of blood biomarkers, a questionnaire, and a computerized STM test. Methods This study was conducted from January 2013 to June 2013, recruiting 90 subjects: 30 breast cancer patients beginning the 3rd of 4th cycles of docetaxel and cyclophosphamide chemotherapy, 30 recovered patients (who completed 4 cycles of docetaxel for a minimum of 6 months), and 30 healthy subjects (disease-free females). The levels of hemoglobin, red and white blood cells, and cortisol in serum, and a computerized STM test were analyzed to estimate the effects of chemotherapy on STM. A questionnaire was given to all subjects to assess quality of life. Results Statistically significant differences were observed for the blood parameters (hemoglobin, red and white blood cells, and cortisol levels) between healthy and on-treatment subjects (respectively 13.47±0.96 g/dL vs 5.37±0.38 g/dL, 4.58±0.41 1012/L vs 2.07±0.13 1012/L, and 6.15±1.03 109/L vs 0.86±0.41 109/L). Scores of the STM test were significantly lower for patients compared to healthy subjects. As indicated by the results of the questionnaire, breast cancer patients had a higher tendency to forget than healthy controls (X2=3.15; p<0.0001) and recovered subjects (X2=3.15; p<0.0001). Conclusion We found depleted levels of hemoglobin, red and white blood cells as a result of chemotherapy, and elevated levels of stress correlated with poor performances in the computerized STM test. A higher cortisol level might be an important precursor of STM deterioration. Monitoring cortisol would be beneficial for evaluating the quality of life of breast cancer patients on chemotherapy.
Tamoxifen does not form detectable DNA adducts in white blood cells of breast cancer patients
