IMPACT OF LETROZOLE TREATMENT ON LIPID PROFILE IN POSTMENOPAUSAL WOMEN WITH HORMONE RECEPTOR-POSITIVE EARLY BREAST CANCER: A PROSPECTIVE STUDY

Document Type : Original Article

Authors

1 Department of Biochemistry and Microbiology, Faculty of Pharmacy, Tishreen University, Lattakia, Syria

2 Department of Oncology, Faculty of Medicine, Tishreen University, Lattakia, Syria.

Abstract

This prospective study aimed to investigate the impact of letrozole treatment on the lipid profile of postmenopausal early breast cancer patients. Sixty postmenopausal women diagnosed with hormone receptor-positive early breast cancer were enrolled in this study. Lipid profile parameters, including TC, LDL-C, HDL-C, and TG, were measured at baseline and at regular intervals during a one-year treatment period with letrozole (2.5 mg/day). Patients' medical history, including previous treatment with tamoxifen, chemotherapy or radiotherapy, was also recorded. All patients have started zoledronic acid through letrozole treatment. Following 4 months of letrozole treatment, a noteworthy increase was observed in TC (p=0.013) and LDL-C (p=0.006) levels compared to baseline values. These elevations reverted to baseline levels after 8 months of treatment. Intriguingly, the observed delayed shifts in TC and LDL-C levels occurred following treatment with zoledronic acid. Furthermore, TC levels decreased significantly after 12 months compared to baseline (p=0.032). HDL-C levels exhibited no significant changes throughout the monitoring periods. TG levels displayed a significant decline after both 8 and 12 months (p=0.015, p=0.018, respectively). Notably, the prior tamoxifen group displayed more pronounced increases in LDL-C and TC levels after 4 months of AI treatment. In contrast, the previous radiotherapy group showed decreased triglyceride levels after 8 and 12 months compared to baseline levels. Letrozole initiation and/or Tamoxifen withdrawal may have adverse effects on lipid profiles, leading to elevated LDL-C and TC levels. Nevertheless, the administration of antiresorption treatment (zoledronic acid) appears to counteract these effects, contributing to an improvement in the lipid profile.

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