Memory impairments with adjuvant anastrozole versus tamoxifen in women with early-stage breast cancer

Abstract

Objective: Hormones have been implicated as modulators of cognitive functioning. For instance, results of our previous work in women with breast cancer showed that cognitive impairment was more severe and involved more memory domains in those who received adjuvant tamoxifen therapy compared with women who received chemotherapy alone or no adjuvant therapy. Recently aromatase inhibitors such as anastrozole have been used in lieu of tamoxifen for the adjuvant treatment of postmenopausal women with hormone receptor-positive, early-stage breast cancer. Plasma estrogen levels are significantly lower in women who receive anastrozole compared with those who receive tamoxifen. We hypothesized, therefore, that anastrozole would have a more profound effect on cognitive function than tamoxifen, a mixed estrogen agonist/ antagonist. Design: To test this hypothesis we compared cognitive function in women with early-stage breast cancer who received tamoxifen with those who received anastrozole therapy in a crosssectional study. We evaluated cognitive function, depression, anxiety, and fatigue in 31 postmenopausal women with early-stage breast cancer who were between the ages of 21 and 65 years and treated with tamoxifen or anastrozole for a minimum of 3 months. Results: The results showed that women who received anastrozole had poorer verbal and visual learning and memory than women who received tamoxifen. Conclusions: Additional, prospective studies are needed to validate and confirm the changes in cognitive function associated with hormone therapy for breast cancer.

Chemotherapy-Related Cognitive Impairment: The Breast Cancer Experience

“…A more recent study was conducted to compare memory impairment seen with adjuvant anastrozole versus tamoxifen for women with early-stage breast cancer (Bender, et al, 2007). Due to evidence to support lower serum estradiol levels with aromatase inhibition compared to selective estrogen receptor modulation, Bender Additional work related to the impact of menopausal symptoms and fatigue to cognitive function was conducted by Tchen, et al (2003).…”

Effect of Endocrine Therapy on Quality of Life and Cognitive Functions in Patients with Breast Cancer

“…Furthermore, the results of a substudy of the ATAC study demonstrated that the anastrozole group had worse verbal memory [21]. In another study, Bender et al [22] evaluated the cognitive functions in patients treated with ET for at least 3 months. Memory as well as verbal and visual learning were poorer with anastrozole in comparison to tamoxifen.…”

Cognitive Performance among Breast Cancer Survivors Treated with Aromatase Inhibitors

“…It is not clear what percentage of the subjects had exposure only to tamoxifen, and not to the AI agent. Bender and colleagues [23] studied 31 postmenopausal women aged 21 to 65, and compared anastrozole recipients to tamoxifen recipients. Some of the women in each group had received cytotoxic chemotherapy.…”