Extended adjuvant hormonal therapy with exemestane has no detrimental effect on the lipid profile of postmenopausal breast cancer patients: final results of the ATENA lipid substudy

Abstract

Introduction Extended adjuvant endocrine therapy for breast cancer with aromatase inhibitors may potentially alter the lipid profile of postmenopausal patients and thus increase the risk of developing cardiovascular disease. In this study, a subprotocol of the ATENA (Adjuvant post-Tamoxifen Exemestane versus Nothing Applied) trial, we compared the effect of the steroidal aromatase inactivator exemestane on the lipid profile of postmenopausal patients with operable breast cancer, in the adjuvant setting, with that of observation alone after completion of 5 to 7 years of primary treatment with tamoxifen.

Exemestane in the Adjuvant Treatment of Breast Cancer in Postmenopausal Women

“…The time to distant recurrence was not improved by exemestane (RR = 0.69; P = 0.13), but 4-year relapse-free survival was significantly longer with exemestane than with placebo (RR = 0.44; P = 0.004). The ATENA trial had enrolled almost 25% of the planned number of patients at the time of study discontinuation 42. Efficacy results from this trial have not yet been published.…”

“…In the ATENA trial, only lipid parameters were reported 42. For the untreated and exemestane groups, total cholesterol and LDL levels increased from baseline to 24 months, and triglyceride levels decreased.…”

Extended adjuvant endocrine therapy in hormone-receptor positive early breast cancer: Current and future evidence

“…This study failed to show any benefit on overall survival, most likely due to the relative short follow-up of 5 years. Two other studies, both evaluating exemestane as extended therapy after 5 years of tamoxifen, were closed prematurely due to the results of the MA.17 trial [40,41]. One of them however published their underpowered results, already showing a borderline significant decrease in DFS at 30 months of follow-up [41].…”

Aromatase inhibitors in the breast cancer clinic: focus on exemestane

“…A TEAM substudy compared the effect of exemestane on lipid metabolism to that of tamoxifen (Markopoulos et al 2005). For triglyceride levels, no significant mean difference across time was seen between tamoxifen and exemestane (Markopoulos et al 2009a). Another randomized study in early breast cancer patients showed no major effect of exemestane on serum lipids compared with placebo (Lønning et al 2005).…”

“…The Study of Letrozole Extension (SOLE) in postmenopausal women with breast cancer is a currently ongoing randomized trial wherein extended continuous letrozole treatment is compared with intermittent letrozole treatment following 4-6 years of prior adjuvant endocrine therapy (Colleoni 2011). The Adjuvant post-Tamoxifen Exemestane vs Nothing Applied (ATENA) trial was an open-label trial in which postmenopausal patients were randomized to 5 years of exemestane treatment or 5 years of observation after 5-7 years of tamoxifen administration (Markopoulos et al 2009a). This trial, however, was prematurely ended because results of the MA.17 trial were published.…”