Strontium-89 combined with doxorubicin in the treatment of patients with androgen-independent prostate cancer

We investigated the activity of a bone-targeting regimen consisting of strontium-89 and doxorubicin in the treatment of patients with androgen-independent prostate cancer. Three and 22 patients with androgen-independent prostate cancer and bone metastasis received doxorubicin at 15 mg/m2 and 20 mg/m2, respectively (intravenously by continuous infusion over 24 hours, once per week). All patients received strontium-89 55 μCi/kg, intravenously, every 3 months. Antitumor activity (a prostate specific antigen decrease of ≥75% from baseline) was seen in 32% of evaluable patients. Clinical benefit based on pain relief and performance improvement was achieved in 76% and 40% of patients, respectively. Strontium-89 combined with doxorubicin can be delivered with acceptable toxicities. Strontium-89 combined with doxorubicin is active in the treatment of androgen-independent prostate cancer and may be useful in future studies designed to optimize organ (bone)-specific therapies.