PhD Scientific Days 2021

CL_III_L: Clinical Medicine III. Lectures

Effects of tamoxifen on cognitive functions in patients with breast cancer. A preliminary cross-sectional study.

Text of the abstract

Introduction: Cognitive side-effects of selective estrogen receptor modulators is a topic of great interest but the phenomenon has remained less understood. Estrogen receptors are found with significant density in brain regions associated with cognition (e.g. prefrontal cortex, hippocampus) and benefits of estrogen on cognition are well known. Whether tamoxifen acts as an antiestrogen or estrogen agonist is tissue-specific and it has mainly been studied in peripheral tissues not in the brain so less is known about the effect of tamoxifen on cognitive domains.

Aim: We aimed to investigate the effects of tamoxifen on domain-specific cognitive functions in a cross-sectional study.

Patients and Methods: We assigned 30 premenopausal and 15 postmenopausal women who were operated with hormone receptor-positive early breast cancer and treated with tamoxifen or tamoxifen and GnRh-antagonist. Neuropsychological assessment contained measurement of complex working memory (Counting Span Test), executive functions (Berg’s Card Sorting Test, Go-No Go Task, Verbal Fluency Tasks), visuo-spatial memory (Corsi block-tapping test), verbal learning and memory (Rey Auditory Verbal Learning Test; RAVLT) and implicit learning (Alternating Serial Reaction Time Task ASRT). We measured anxiety (STAI), depression (Beck) and perceived/subjective cognitive function (FACT-Cog). Data were compared to an age- and educational- level matched healthy control group (25 premenopausal and 21 postmenopausal women). Mann-Whitney U-test and repeated measures ANOVA were used for statistical analysis.

Results: All groups showed evidence of implicit learning, but in the healthy premenopausal group we found significant decreased level of accuracy in the time course of implicit learning than in the treated group (p=0.013). The premenopausal treated group had a higher performance than the healthy controls in the executive function task (Berg’s Card Sorting Test). In the same task the postmenopausal treated group was weaker than the healthy control (all p<0.05). Groups did not differ from each other in anxiety, depression and perceived/subjective cognitive function.

Conclusion: Our findings suggest that tamoxifen affects cognitive functions such as striatal dependent implicit learning and dorsolateral prefrontal cortex dependent executive function, but it’s effect depends on the menopausal status.

University and Doctoral School

Semmelweis University, Károly Rácz Doctoral School of Clinical Medicine