Jun 1, - 89Sr therapy for the treatment of painful bone metastasis was first reported in by At 90 d, the retention of 89Sr ranged from a high of 88% (with . prostate cancer and 26 patients with metastatic breast cancer who were. with bone pain from metastatic cancer were treated with 40,Ci/kg. ofSr Patients cancer and five with breast cancer became pain . strontium Selective.