ANTIATHEROGENIC EFFECTS OF ADJUVANT ANTIESTROGENS - A RANDOMIZED TRIAL COMPARING THE EFFECTS OF TAMOXIFEN AND TOREMIFENE ON PLASMA-LIPID LEVELS IN POSTMENOPAUSAL WOMEN WITH NODE-POSITIVE BREAST-CANCER

Purpose: To evaluate whether a novel antiestrogen, toremifene, has sim ilar antiatherogenic effects as tamoxifen. Patients and Methods: Forty -nine postmenopausal patients with node-positive breast cancer were ra ndomized in a trial that compared the effects of tamoxifen and toremif ene on serum lipoproteins. Tamoxifen was given at 20 mg and toremifene at 60 mg orally per day for 3 years. Serum concentrations of apolipop rotein (apo) A-I, A-II, and B, and lipoprotein(a) [Lp(a)], cholesterol , triglyceride, high-density lipoprotein (HDL) cholesterol, low-densit y lipoprotein (LDL) cholesterol, follicle-stimulating hormone (FSH), l uteinizing hormone (LH), and estradiol were measured before and after 12 months of antiestrogen therapy. Results: Both antiestrogens signifi cantly reduced serum and LDL cholesterol and apo B levels. However, th e response of HDL cholesterol to treatments was clearly different betw een the groups. Toremifene increased the HDL level by 14%, whereas tam oxifen decreased it by 5% (P=.001). As a consequence, both cholesterol -to-HDL and LDL-to-HDL ratios decreased more in the toremifene than ta moxifen group (P=.008 and P=.03, respectively). Toremifene also increa sed the apo A-I level (P =.00007) and apo A-I-to-A-II ratio (P=.018). Both tamoxifen and toremifene decreased the Lp(a) concentration signif icantly (change, 34% v 41%). Conclusion: These results provide positiv e evidence that toremifene has antiatherogenic properties with potency to improve all lipoproteins that are associated with increased corona ry heart disease (CHD) risk. (C) 1996 by American Society of Clinical Oncology.