Cognitive function in postmenopausal breast cancer patients one year after completing adjuvant endocrine therapy with letrozole and/or tamoxifen in the BIG 1-98 trial

Kelly-Anne Phillips, Julie Aldridge, Karin Ribi, Zhuoxin Sun, Alastair Thompson, Vernon Harvey, Beat Thuerlimann, Fatima Cardoso, Olivia Pagani, Alan S. Coates, Aron Goldhirsch, Karen N. Price, Richard D. Gelber, Juerg Bernhard

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    48 Citations (Scopus)


    Endocrine therapy for breast cancer may affect cognition. The purpose of this study was to examine whether cognitive function improves after cessation of adjuvant endocrine therapy. Change in cognitive function was assessed in 100 postmenopausal breast cancer patients in the BIG 1-98 trial, who were randomized to receive 5 years of adjuvant tamoxifen or letrozole alone or in sequence. Cognitive function was evaluated by computerized tests during the fifth year of trial treatment (Y5) and 1 year after treatment completion (Y6). Cognitive test scores were standardized according to age-specific norms and the change assessed using the Wilcoxon signed-rank test. There was significant improvement in the composite cognitive function score from Y5 to Y6 (median of change = 0.22, effect size = 0.53, P < 0.0001). This improvement was consistent in women taking either tamoxifen or letrozole at Y5 (P = 0.0006 and P = 0.0002, respectively). For postmenopausal patients who received either adjuvant letrozole or tamoxifen alone or in sequence, cognitive function improved after cessation of treatment.

    Original languageEnglish
    Pages (from-to)221-226
    Number of pages6
    JournalBreast Cancer Research and Treatment
    Issue number1
    Publication statusPublished - Feb 2011


    • Cognitive function
    • Breast cancer
    • Aromatase inhibitor
    • Tamoxifen
    • Letrozole
    • Quality of life
    • WOMEN

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