Effect of aromatase inhibitors on lipid metabolism, inflammatory response and antioxidant balance in patients with breast carcinoma.

BACKGROUND Aromatase inhibitors may affect lipid metabolism, inflammatory response and antioxidant balance. PATIENTS AND METHODS One hundred and eighty-six post-menopausal patients with breast carcinoma underwent evaluation of parameters of lipid metabolism, inflammatory response and antioxidant balance immediately before as well as 2 and 4 months after the start of therapy with aromatase inhibitors. RESULTS A significant increase in total, very low density lipoprotein (VLDL) and low density lipoprotein (LDL) cholesterol, lipoprotein (a), retinol, C-reactive protein and fibrinogen was observed. The changes of serum lipid concentrations were restricted mostly to the patients pre-treated with tamoxifen who had significantly lower baseline levels of these parameters. CONCLUSION An increase of serum cholesterol, lipoprotein (a), C-reactive protein and fibrinogen in patients treated with aromatase inhibitors is the result of tamoxifen withdrawal rather than a direct effect of therapy. No significant changes in serum lipids were observed in patients treated with aromatase inhibitors in the first-line setting.