Original article The effects on lipid serum levels of a 2-year adjuvant treatment with exemestane after tamoxifen in postmenopausal women with early breast cancer A. Montagnani a, ⁎ , S. Gonnelli a , A. Cadirni a , C. Caffarelli a , K. Del Santo a , C. Pieropan a , M.S. Campagna a , M. Montomoli a , R. Petrioli b , R. Nuti a a Department of Internal Medicine, Endocrine-Metabolic Sciences and Biochemistry, University of Siena, Italy b Department of Human Pathology and Oncology, Medical Oncology Section, University of Siena, Italy Received 9 February 2007; received in revised form 29 April 2007; accepted 6 May 2007 Available online 1 April 2008 Abstract Background: The third-generation aromatase inhibitor exemestane represents a new development in the treatment of estrogen-positive breast cancer. The aim of this study was to evaluate the effects on lipid profile and body composition of the shift from tamoxifen to exemestane. Methods: After 2–3years of tamoxifen adjuvant treatment, 68 postmenopausal women were randomly assigned to either continue tamoxifen 20 mg/day (n = 35) or to switch to exemestane 25 mg/day (n = 33). Results: No significant changes in lipid profile were found in patients continuing on tamoxifen. In the exemestane group, serum HDL-cholesterol (HDL-C) and triglycerides (TG) decreased significantly (p b 0.01) and serum LDL-cholesterol (LDL-C) increased significantly (p b 0.05) with respect to baseline. The difference between the two groups was significant. Moreover, in the exemestane group, fat mass (FM) and fat-free mass (FFM) showed an opposite trend, which determined a progressive and significant increase in the FFM/FM ratio. Conclusion: This study shows that the choice of first-line treatment or adjuvant therapy for breast cancer should also take the individual lipid and body composition profile into account. © 2008 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved. Keywords: Lipid profile; Body composition; Aromatase inhibitors; Breast cancer; Cardiovascular risk 1. Introduction Breast cancer is the major health problem for women in the Western world [1]. Since a large part of breast tumors are estrogen-dependent, estrogen receptors and estrogen synth- esis represent two important targets for therapy [2]. For many years, tamoxifen, taken for 5years, has been the gold standard adjuvant therapy for postmenopausal women with endocrine-responsive early breast cancer [3]. However, several trials have reported that, while tamoxifen has been shown to have a generally favorable safety profile, long-term tamoxifen therapy is associated with serious risks, such as endometrial cancer and thromboembolic events. Such risks are thought to be a consequence of the partial estrogen agonist activity of tamoxifen in certain tissues [4]. The limitations of tamoxifen have prompted research into alternative endocrine therapies with increased efficacy and fewer long-term complications. Third-generation non-ster- oidal aromatase inhibitors, such as anastrozole and letrozole, and the third-generation steroidal aromatase inactivator exemestane are highly selective for aromatase and almost completely block estrogen synthesis [5]. Recent reports have clearly established the value of aromatase inhibitors as adjuvant therapy for postmenopausal women with endo- crine-responsive early breast cancer [6–8]. Based on this, the European Journal of Internal Medicine 19 (2008) 592 – 597 www.elsevier.com/locate/ejim ⁎ Corresponding author. Fax: +39 0577 233347. E-mail address: amontagnani@unisi.it (A. Montagnani). 0953-6205/$ - see front matter © 2008 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved. doi:10.1016/j.ejim.2007.05.016