Mitoxantrone: new indication. More risky than beneficial in advanced prostate cancer

(1) The reference management of advanced-stage hormone-resistant prostate cancer is palliative treatment aimed at controlling pain and improving quality of life, namely analgesics and radiotherapy for painful bone metastases. (2) Mitoxantrone, a cytotoxic agent, has been granted marketing authorisation in this indication. Estramustine was already available in this setting. (3) The clinical assessment file on mitoxantrone mainly comprises two unblinded trials comparing a steroid + mitoxantrone combination with steroid alone. Mitoxantrone has not been compared with palliative care comprising radiotherapy. (4) One trial involved 161 patients with painful metastases. They were treated either with prednisone (10 mg/day by mouth) + mitoxantrone (12 mg/m2 intravenously every 3 weeks), or with prednisone alone. The other trial involved 242 patients with metastases that were not always symptomatic, who were treated either with hydrocortisone (40 mg/day orally) + mitoxantrone (14 mg/m2 intravenously every three weeks) or with hydrocortisone alone. (5) No trial showed a benefit of mitoxantrone in terms of the duration or quality of survival. The analgesic effect of mitoxantrone in the first trial was moderate, benefiting fewer than 20% of patients. The evidence shows that radiotherapy is effective in 80% of cases. (6) The main adverse effects of mitoxantrone are haematological and cardiovascular. The adverse effect profile of mitoxantrone does not appear to be any more favourable than that of radiotherapy. (7) In practice, for patients with advanced-stage hormone-resistant prostate cancer the reference palliative treatment for painful bone metastases remains analgesics plus radiotherapy. Mitoxantrone is of no use in this setting.