Neurological effects of endocrine therapy in the treatment of breast cancer

Abstract

1 in 8 women will suffer from breast cancer in their lifetime. Roughly three quarters of breast cancers can be classified as estrogen receptor-positive(ER+). Patients with ER+ tumors receive adjuvant endocrine therapy, in the form of selective estrogen receptor modulators(SERMs) or aromatase inhibitors(AIs), which prevent the synthesis of estrogen. The use of endocrine therapy has been associated with neurological and cognitive side effects, particularly problems with memory. Experimental and clinical data are conflicting, however. Experimental data indicates that SERMs act like estrogen and have beneficial effects on the brain, while AIs stop estrogen production and therefore have adverse cognitive effects. Clinical data however indicates that SERMs have adverse side effects, while AIs don’t affect memory and cognition as much as would be expected.