Treatment with bone-targeted alpha-emitting but not beta-emitting radioisotopes is associated with a significant improvement in overall survival and symptomatic skeletal event (SSE)-free survival among patients with bone metastases from castration-resistant prostate cancer (CRPC), according to a new study published in JAMA Oncology.
In a meta-analysis of data from 6 randomized clinical trials that included 2081 patients with bone metastases from CRPC, Gwénaël Le Teuff, PhD, of Institute Gustave Roussy in Villejuif, France, and colleagues found that, compared with no radioisotope use, treatment with the alpha emitter radium-223 was associated with a significant 30% decreased risk of death, whereas use of the beta emitter strontium-89 did not confer a significant survival benefit.
In addition, radium-223 treatment was associated with a significant 35% decreased risk of SSES, whereas strontium-89 treatment did not result in a significant decrease in the risk of SSEs.
In subgroup analyses, patients with the lowest serum PSA values appeared to benefit significantly more from bone-targeted radioisotope therapy compared with those who had the highest serum PSA values, according to the investigators.
Because of the heterogeneity between trials, caution is needed in generalizing results, Dr Le Teuff’s team noted.
Terrisse S, Karamouza E, Parker CC, et al. Overall survival in men with bone metastases from castration-resistant prostate cancer treated with bone-targeted radioisotopes [published online December 12, 2019]. JAMA Oncol. doi: 10.1001/jamaoncol.2019.4097