Adverse effect of letrozole on lipid profile in postmenopausal breast cancer patients

Back ground: Letrozole, a third generation aromatase inhibitor, is considered superior to tamoxifine in the treatment of all stages of breast cancer. The decrease in estrogen levels due to letrozole treatment is found to have an adverse effect on lipid profile. Data regarding the effect of duration of letrozole treatment on lipid profile is limited. The present study was indented to study the effect of letrozole treatment on total cholesterol, LDL cholesterol, HDL cholesterol and triacylglycerol in postmenopausal breast cancer patients at baseline and after 3 months.
Material and methods: Ninety five Postmenopausal estrogen receptor positive breast cancer patients receiving letrozole were recruited. Patients with hypothyroidism, diabetes mellitus, liver or renal disease, proteinuria, alcoholism, patients taking drugs known to influence lipid metabolism were excluded. 5 ml of venous sample was collected at baseline and after 3 months of letrozole treatment for lipid profile analyses. Paired t-test was used to compare baseline line and 3 months data.
Results: The mean age of the study subjects was 55.80 ± 8.63 years. There was a statistically significant increase in the level of total cholesterol (p= 0.02), LDL-C (p=0.00) and decrease in the level of HDL-C (p=0.00), atherogenic risk ratios: Log (total cholesterol/HDL-C) (P<0.005) and LDL -C/HDL - C (P<0.005) after 3 months of letrozole treatment. There was no difference in the levels of TAG and VLDL-C.
Conclusion: We conclude that letrozole at a dose of 2.5mg per day for three months has an adverse effect on the serum lipid profile in postmenopausal women with breast cancer