Strontium-89 therapy and imaging with bremsstrahlung in bone metastases

The bone-seeking radiopharmaceutical Sr-89 has been used as a palliative treatment for patients with bone pain caused by bone metastases. The authors report the results of nine patients (three with prostate cancer, four with breast cancer, one with thyroid cancer, and one with lung cancer) who underwent therapy with Sr-89 chloride for painful bone metastases, and evaluate Sr-89 imaging with bremsstrahlung. Two levels of dosage (1.5 and 2.2 MBq/kg) were used. Sr-89 imaging was performed in seven patients 1 week after injection. Abnormal uptake was seen in all and was consistent with the results of Tc-99m HMDP imaging. Six patients were assessed at 3 months and three patients toward the time they were terminal; 78% (seven of nine) derived some benefit. Two patients had a favorable clinical response and showed improvement on Tc-99m HMDP imaging.