Effects of Tamoxifen and Exemestane on Cognitive Function in Postmenopausal Patients with Breast Cancer
Menée à partir de données portant sur 206 patientes atteintes d'un cancer du sein après la ménopause, cette étude évalue l'effet, sur leurs fonctions cognitives, d'un traitement combinant ou non exémestane et tamoxifène
Résumé en anglais
Background: Cognitive effects of tamoxifen have been described. We augment data from a previous short-term (ST) follow-up study with long-term (LT) data to evaluate ST and LT cognitive effects of tamoxifen followed by exemestane and exemestane in breast cancer patients.
Methods: Patients from the Tamoxifen and Exemestane Adjuvant Multinational trial received 5 years exemestane (exemestane group, n = 114) or 2.5 years tamoxifen followed by 2.5 years exemestane (sequential group, n = 92). Neuropsychological performance was assessed pre-endocrine therapy, after 1 year (ST follow-up) and at 5 years (LT follow-up). Controls (n = 120) were assessed with parallel intervals. With random effects modeling we evaluated cognitive changes from baseline to ST and LT follow-up. Statistical tests were 2-sided.
Results: After controlling for age, intelligence quotient, attrition, menopausal symptoms, anxiety and/or depression, and/or fatigue, the sequential group showed ST and LT decline compared with controls on verbal memory (effect size [ES] = 0.26, P = .01; ES = 0.34, p = .003) and executive function (ES = 0.27, p = .007; ES = 0.38, p = .002). Compared with the exemestane group, the sequential group demonstrated ST decline on information processing speed (ES = 0.33; p = .01) and executive function (ES = 0.32; p = .01) and LT decline on verbal memory (ES = 0.33; p = .02). The exemestane group showed no cognitive decline compared with controls.
Conclusion(s): Cognitive adverse effects of tamoxifen alone and after switching to exemestane were observed, suggestive of a carryover effect of tamoxifen. Our results underline the need for well-controlled, prospective trials studying cognitive effects of endocrine therapy.
