[Use of strontium-89 in the analgesic treatment of bone metastases].

The analgesic properties of 89Sr were investigated in 17 patients with multiple painful bone metastases. 89Sr is a radioisotope, the metabolism of which in the body is comparable to that of calcium. It is a pure beta emitter and its half-life is 51 days. When injected intravenously it is captured by bone, especially at locations where the turnover is increased. Each patient received 1--2 mCi of 89Sr. Bone scans and hematological investigations were performed before, and 2 months after, treatment. No significant changes were found. Shealy's method was used to assess pain, initially twice a week and then at more prolonged intervals. One patient suffering from multiple myeloma showed a spectacular improvement and 6 others responded favourably. Improvement generally occurred within 3--7 days, but was sometimes delayed for up to 3 weeks. Relief lasted for up to several months. Five patients had an increase of pain during the 24 hours immediately after treatment. An average of 28% of the administered radioactive dose was found in the urine collections during the first 48 hours. Although the treatment was not successful in every case, the use of 89Sr as a long acting analgesic in multiple bone metastases should be considered more frequently, especially as there are no side effects.