Side effects of androgen deprivation therapy: monitoring and minimizing toxicity

The current trends in favor of androgen deprivation therapy (ADT) for nonmetastatic prostate cancer at the stage of biochemical recurrence or increasing prostate-specific antigen (PSA) raises the issue of exposing otherwise asymptomatic patients to potential side effects over the longer term. Some of these side effects can have deleterious effects on quality of life, and others may contribute to increased risks for serious health concerns associated with aging. Sexual side effects are the most well-recognized adverse effects from ADT and include loss of libido, erectile dysfunction (ED), and hot flashes. Loss of libido is distressing to many men, and they may not pursue treatments for ED. However, for those who do maintain sexual interest, various remedies are available. The incidence of hot flashes, which may not abate over the course of ADT, is close to 80%. Estrogens, progestin megestrol acetate, medroxyprogesterone acetate, venlafaxine, and cyproterone acetate have been shown to alleviate hot flashes and associated symptoms. Physiologic effects, including gynecomastia, changes in body composition (weight gain, reduced muscle mass, increase in body fat), and changes in lipids, are less commonly recognized as side effects of ADT. These may lead to an exacerbation of potentially more serious conditions, such as hypertension, diabetes, and coronary artery disease. Loss of bone mineral density, anemia, and hair changes also may occur. Additionally, both the diagnosis of prostate cancer and the hormonal therapy can cause psychological distress. These side effects need more systematic study in clinical trials. Physicians should be aware of far-reaching consequences of ADT and should incorporate strategies for preventing and managing toxicities into routine practice.