Cognitive impairment after cytotoxic chemotherapy

Abstract

Background Neurotoxicity is a frequent side effect of cytotoxic chemotherapy and affects a large number of patients. Despite the high medical need, few research efforts have addressed the impact of cytotoxic agents on cognition (ie, postchemotherapy cognitive impairment; PCCI). One unsolved question is whether individual cytotoxic drugs have differential effects on cognition. We thus examine the current state of research regarding PCCI. Neurological symptoms after targeted therapies and immunotherapies are not part of this review. Methods A literature search was conducted in the PubMed database, and 1215 articles were reviewed for predefined inclusion and exclusion criteria. Thirty articles were included in the systematic review. Results Twenty-five of the included studies report significant cognitive impairment. Of these, 21 studies investigated patients with breast cancer. Patients mainly received combinations of 5-fluorouracil, epirubicin, cyclophosphamide, doxorubicin, and taxanes (FEC/FEC-T). Five studies found no significant cognitive impairment in chemotherapy patients. Of these, 2 studies investigated patients with colon cancer receiving 5-fluorouracil and oxaliplatin (FOLFOX). Independent risk factors for PCCI were patient age, mood alterations, cognitive reserve, and the presence of apolipoprotein E e4 alleles. Conclusions There is evidence that certain chemotherapy regimens cause PCCI more frequently than others as evidenced by 21 out of 23 studies in breast cancer patients (mainly FEC-T), whereas 2 out of 3 studies with colon cancer patients (FOLFOX) did not observe significant changes. Further studies are needed defining patient cohorts by treatment protocol in addition to cancer type to elucidate the effects of individual cytotoxic drugs on cognitive functions.

Cognitive Functioning and its Associated Factors among Breast Cancer Patients on Chemotherapy at Tikur Anbessa Specialized Hospital, Addis Ababa Ethiopia: An Institution-Based Comparative Cross-Sectional Study

“…Unlike other studies, in the current study, there was no association between MMSE cognitive score and the number of chemotherapy cycles taken, type of chemotherapy regimen, and the stage of breast cancer (21)(22)(23). This may be due to differences in the method of cognitive assessment used and the difference in disease and treatment status of the patients.…”

Cognitive Effects and Depression Associated With Taxane-Based Chemotherapy in Breast Cancer Survivors: A Meta-Analysis

“…This report was not included in our analysis because it was not limited to taxanes but included other agents such as vinca alkaloids, anthracyclines, platinum compounds, topoisomerase inhibitors, and bleomycin and mitomycin (66). In addition, this report did not subdivide the cognitive changes into domains, but rather showed overall decreased cognitive function (66). Nonetheless, a similar pattern of CICI was reported compared with that which we observed.…”

“…In 2019, a systematic review investigating cognitive impairment after cytotoxic chemotherapy examined 21 studies with enrolled patients with breast cancer (66). This report was not included in our analysis because it was not limited to taxanes but included other agents such as vinca alkaloids, anthracyclines, platinum compounds, topoisomerase inhibitors, and bleomycin and mitomycin (66). In addition, this report did not subdivide the cognitive changes into domains, but rather showed overall decreased cognitive function (66).…”

Effect of Chemotherapy and Radiotherapy on Cognitive Function in Colorectal Cancer: Evidence from National Representative Longitudinal Database

“…A recent systematic review on cognitive impairment after cytotoxic chemotherapy demonstrated that two out of three studies on colon cancer treated with FOLFOX had not observed cognitive changes, whereas 21 out of 25 studies on breast cancer had detected cognitive impairment after cytotoxic chemotherapy. [21] The findings imply that characteristics of primary tumor, both biological and psychosocial, play important role on manifestation of chemotherapy-related cognitive impairment. It is well known that a significant proportion of breast cancer patients suffer from depression and anxiety, which leads to dysfunctional cognition and general fatigue.…”