Evaluating the effects of chemotherapy on cognitive function in patients with early breast cancer

The study evaluated the contribution of chemotherapy on cancer-related cognitive impairment (CRCI) reported by women with early breast cancer. The authors found that chemotherapy added to hormonal therapy caused early and short-term CRCI in such patients, compared to hormonal therapy alone.

CRCI refers to problems in brain functions (memory, reasoning, concentration) due to cancer and its therapy. CRCI is linked to a decrease in health-related quality of life (HRQL) in patients with cancer. CRCI was previously reported in women with breast cancer on chemotherapy. Whether it was caused by chemotherapy alone is unclear. Analyzing CRCI from patients’ perspectives is also important.

The study included women with hormone-positive, HER2-negative, and node-negative early breast cancer. 218 patients were given chemotherapy plus endocrine (hormonal) therapy (CT+E group). 236 patients received hormonal therapy alone (E group). As E-therapy, 58% of women received aromatase inhibitors and 37% received tamoxifen (Nolvadex). The most common chemotherapy was docetaxel (Taxotere) + cyclophosphamide (Cytoxan) or anthracycline-based. CRCI was measured by the FACT-Cog scale. Lower scores signify more CRCI. It was assessed through questionnaires filled out by patients.

Both groups experienced a decline in CRCI during treatment compared to before treatment. The CT+E group had a greater decline in CRCI from beginning to 3 and 6 months of therapy, compared to E alone.

CRCI was reported by 36.7% of women in CT+E and 26.3% of women under E at 3 months. However, the changes in CRCI scores at 12, 24, and 36 months of therapy were similar in both groups. CRCI was not linked to whether women were before or after their menopause.

The study concluded that chemotherapy added to hormonal therapy caused higher cognitive impairment compared to hormonal therapy alone, at 3 and 6 months in patients with early breast cancer. The authors suggest that these changes did not last past 12 months of treatment. 

The cognitive function was assessed by patient questionnaires. There may be bias related to this form of evaluation.