TAMOXIFEN IN LIVER-DISEASE - POTENTIAL EXACERBATION OF HEPATIC-DYSFUNCTION

Tamoxifen, a non-steroidal anti-estrogen, has been used successfully f or a decade as post-operative adjuvant therapy for breast cancer. Tamo xifen is generally well tolerated with few side effects, especially at the typical dose of 10 mg twice daily. However, hepatic effects have been reported after tamoxifen administration and are usually found to be cholestatic in nature. Although previous reports concentrate on tam oxifen as a probable cause of drug-induced hepatotoxicity, very little attention has been focused on the use of tamoxifen in patients with p re-existing liver dysfunction and the possible need for dose adjustmen t. We present the case of a 48-year-old woman with an acute exacerbati on of her pre-existing liver dysfunction and subsequent elevations of tamoxifen blood levels after approximately one year of tamoxifen thera py for adjuvant treatment of breast cancer. Tamoxifen dosing was adjus ted based on serum levels.