Source: DGNews  |  Posted 8 years ago

By Cameron Johnston

COPENHAGEN, DENMARK -- October 1, 2003 -- The breast pain and gynaecomastia that are commonly associated with use of antiandrogen agents for prostate cancer can be largely alleviated with 2 short doses of low-energy radiotherapy, doctors in Belgium have found.

The antiandrogen agent bicalutamide is commonly used to treat prostate cancer and has a proven track record of helping to significantly reduce the risk of disease progression if initiated early enough and if the cancer has not metastasised, explained Hein van Poppel, MD, PhD, Gasthuisberg University Medical School, Leuven, Belgium here September 22nd at ECCO 12: The European Cancer Conference.

According to Dr. van Poppel, however, breast abnormalities are common with this therapy caused by an imbalance in the stimulatory effect of oestrogen and the inhibition of androgen in the breast.

In this study, 51 patients with histologically confirmed prostate cancer, no metastases, and no nodal involvement received bicalutamide 150 mg/day. Of these, 3 patients developed gynaecomastia, 14 had breast pain, and 24 developed both.

The men who these adverse effects were treated with 2 fractions of radiotherapy, 6 Gy each, on consecutive days. The radiotherapy was directed in a 5-cm circle around the nipple and from the skin surface into the underlying muscle. Treatment was initiated as soon as possible after the development of symptoms, and usually followed complaints or a request for help from the patient, Dr. van Poppel said.

Following radiotherapy, patients were monitored for 14 days, and then were seen at 3 and 6 months to assess the efficacy of the bicalutamide and the outcomes of the radiation therapy.

In all, 33.3% of the patients who were treated for gynaecomastia experienced an improvement or resolution of the condition, while another 33.3% worsened and 25.9% had no change in their symptoms.

Among the 38 who were treated for breast pain, 39.5% had improvement or resolution of symptoms, symptoms worsened in 21.1%, and 31.6% had no change. The numbers do not include the entire cohort in the study, because some patients had inconclusive or inconsistent results, Dr. van Poppel said.

There were no severe adverse reactions to the radiation therapy, with 45% of patients experiencing mild or moderate reactions, including breast or nipple erythema and skin irritation. These conditions all resolved within 5 weeks of treatment, he said.

Dr. van Poppel concluded that radiotherapy can be a useful means of treating the symptoms of breast pain and gynaecomastia caused by antiandrogens treatments in patients with prostate cancer.

Given that past studies have shown that these 2 adverse effects of antiandrogen therapy increase over time, early treatment is advised. Not all patients will respond, however, and the conditions are actually alleviated in only around one-third of patients who undergo this treatment.

[Study title: Efficacy and Tolerability of Radiotherapy as Treatment for Bicalutamide-Induced Breast Pain and Gynaecomastia in Prostate Cancer. Abstract 881]