Duration of tamoxifen effect on lipidemic profile of postmenopausal breast cancer patients following deprivation of treatment

OBJECTIVE: It was the aim of this study to investigate the effect of tamoxifen withdrawal on markers of lipid metabolism in postmenopausal women with breast cancer who completed tamoxifen therapy and received no further treatment. METHODS: Lipidemic profile changes were studied in 190 postmenopausal patients with operable breast cancer, following cessation of 5-7 years of tamoxifen treatment. Assessments of total cholesterol, high-density lipoprotein, low-density lipoprotein and total serum triglycerides were performed at baseline, 6 months and 12 months. RESULTS: By 6 months, both total cholesterol and low-density lipoprotein levels were significantly increased, and total triglyceride levels were significantly reduced compared with baseline values and maintained to 12 months. There was no significant alteration observed for high-density lipoprotein levels over the study period. CONCLUSION: The beneficial effect of tamoxifen on the lipidemic profile of postmenopausal breast cancer patients seems to be lost in less than 12 months time following cessation of 5-7 years of tamoxifen treatment. A 'rebound effect' on the lipidemic parameters should be expected and those patients should be monitored carefully.