A new article on the OncologySTAT web site provides a summary of a presentation by Alain Pecking, MD, from the annual meeting of the International Society for Geriatric Oncology. Dr. Pecking’s presentation was based on his 18-year experience of using strontium-89 in the treatment of 841 prostate cancer patients with painful, late-stage, bone metastases.
In this series of patients, a complete response was defined as the absence of pain from > 80 percent of all painful, metastatic bone sites and a significant decrease in the use of narcotic analgesics; a partial response was defined as a reduction in pain from > 40 percent of all painful, metastatic bone sites without any significant reduction in the daily use of narcotic analgesics; a slight change, no change, or an increase in the use of narcotic analgesics was regarded as treatment failure.
Key findings included the following:
- The average (median) age of the patients in Dr. Pecking’s series was 73 years.
- For patients who showed a complete or a partial response to a first injection of strontium-89, it was possible to give one or two additional injections of this radionuclide.
- In Pecking’s series
- A second infusion was given to 268/841 patients (31.9 percent; median age, 71 years).
- A third infusion was given to 86/841 men (10.2 percent; median age, 70 years).
- Patients who received one or two infusions had 12 to 16 metastatic sites, of which about 4 were painful.
- Patients who received three infusions had about 7 painful metastatic sites.
- “Good” responses (i.e., the total number of complete and partial responses) were reported as follows:
- After one infusion the complete response rate was 12.6 percent and the partial response rate was 50.4 percent (total response rate, 63.0 percent).
- After two infusions the complete response rate was 21.4 percent and the partial response rate was 53.7 percent (total response rate (75.1 percent).
- After three infusions the complete response rate was 15.1 percent and the partial response rate was 43.0 percent.
- Average times to response were
- 11 days after one infusion
- 14 days after a second infusion
- Just over 15 days after a third infusion
- The average duration of the pain-easing effect after each dose was
- 158 days after the first infusion
- 138 days after a second infusion
- 101 days after a third infusion
- A number of side effects were carefully noted by Dr. Pecking.
- Pain was a common side effect of treatment, and was reported within the first 15 days after an infusion by < 25 percent of patients.
- PSA levels increased after the first infusion of strontium-89 in 681/841 patients (81.0 percent).
- Spine neurologic syndrome occurred in 3/841 patients (0.4 percent) within 4 months after the infusion.
- Colitis was observed in 4.8 percent of patients.
- Grade 2 to 4 platelet toxicity was observed in 5.1, 11.9, and 13.2 percent of patients after the first, second, and third infusions.
There is now reasonably extensive experience with the use of strontium-89 and other forms of radionuclide therapy of painful bone metastases. While this form of pain management may not be appropriate for all patients, and it is clearly associated with some risk for adverse reactions, it can also significantly improve quality of life for well over 50 percent of men with metastasis-related bone pain. As Dr. Pecking also noted in his presentation, the side effects of other forms of treatment for bone pain (i.e., opiate drugs) also have a significant range of side effects, including fatigue, nausea, constipation, and anorexia.
A key question for the future will be whether the use of the radionuclide radium-223 can offer a similar level of relief from bone pain while simultaneously offering the survival benefit already established in a previously reported clinical trial.