Effects of tamoxifen on cognition and language in women with breast cancer: A systematic search and a scoping review.

Objective Breast cancer treatments bring adverse consequences that interfere with everyday functioning. Importantly, some of these treatments are associated with cognitive and language changes. Tamoxifen is a selective estrogen receptor modulator and is a common endocrine therapy treatment for breast cancer. The current review examines the specific domains of cognition and language affected by the use of tamoxifen in women with breast cancer. Methods We conducted a systematic search that examined cognitive and/or language functions in chemotherapy-naive women with breast cancer taking tamoxifen. PubMed, Cochrane CENTRAL, CINAHL Complete, PsycINFO, Scopus, EMBASE, and the Grey Literature Report (greylit.org) were searched. Covidence Systematic Review software (covidence.org) was used to manage the screening process of study titles and abstracts as well as full texts. A total of 17 studies were included in the review. Results A range of cognitive and language domains were reported. These were grouped into seven broad domains: attention, memory, speed, executive functioning, verbal abilities, visual abilities, and language abilities. Results showed that there is compelling evidence that specific domains of memory and speed are negatively affected by the use of tamoxifen. In addition, there was a pattern of change in domains of executive functions and verbal abilities. Conclusions Tamoxifen affects specific cognitive and language domains. Language domains beyond semantics have not been studied and thus conclusions related to these domains, and language in general, could not be made. Studies exploring the effects of tamoxifen on the different domains of language are recommended.