Strontium 89 for palliation of bone metastases.

At the University of Kansas Medical Center, systemic use of strontium 89 ((89)Sr), a betaemitting radioisotope, was evaluated in the treatment of metastatic carcinoma to bone for relief of bone pain. Eighty-five patients were treated with systemic (89)Sr in the dosage of 30 to 40 μCi/kg. All patients had multiple bone metastases, the majority with primary breast or prostatic cancer. The response to treatment was evaluated by daily diary entries, changes in the amount of pain medication, periodic bone scans, and other laboratory values.In the patients who survived (47) and who were observed for three or more months, overall results showed 15 percent becoming pain free; 23 percent showed marked improvement with decreased consumption of pain medication; 53 percent showed mild but significant improvement in pain relief and decrease in pain medication requirement; and 9 percent showed no improvement. No patients noted a worsening of bone pain after the treatment. There was a combined favorable response in 91 percent (43/47) of patients with some meaningful palliation after (89)Sr therapy. This study, using (89)Sr systemic therapy, suggests that this isotope may be a valuable adjuvant therapy for palliation of pain from metastatic bone lesions.