Avascular necrosis of the femoral head in patients with prostate cancer treated with cyproterone acetate and radiotherapy.

We report the case histories of two patients with histologically confirmed adenocarcinoma of the prostate, both of whom had been treated with steroidal anti-androgen therapy in the form of cyproterone acetate prior to radical or palliative pelvic irradiation, and who subsequently developed femoral head avascular necrosis. This is a diagnosis that should be considered in patients with prostate cancer who present with hip pain in the absence of biochemical evidence of disease progression.