Radium-223 treatment for metastatic prostate cancer increases fracture risk: Study

London, UK: According to a new study, men with metastatic castration-resistant prostate cancer (mCRPC), particularly those treated with radium-223, are at risk of fracture. The findings of this study were published in the journal Clinical Genitourinary Cancer.

Radium-223 is an alpha-emitting radionuclide that seeks out bone and is used to treat metastatic castration-resistant prostate cancer. When used with abiraterone and prednisolone, radium-223 increases the risk of fracture. It is unknown if males getting radium-223 monotherapy are at risk of fracture.

Adham Hijab and the team conducted the study with the objective to describe the risk of fracture in males who were given radium-223 as a single agent. In addition, the fracture risk in a similar sample of males with mCRPC who were scanned in the same way but did not receive radium-223 was evaluated as a baseline. 

This study was a prospective, multicenter phase II trial of radium-223 in 36 males with mCRPC and a reference cohort (n = 36), matched for fracture risk but not treated with radium-223. Whole-body magnetic resonance imaging was used to evaluate bone fractures. The key result was the possibility of additional fractures.

The key findings of this study were as follow:

1. Radium-223 was administered to 36 individuals in up to six 4-week cycles.

2. In 20 patients with a median follow-up of 16.3 months, 74 additional fractures were discovered.

3. At 12 months, the freedom from fracture was 56%.

4. Prior corticosteroid usage was linked to a higher incidence of fracture in a multivariate study.

5. Over a median follow-up of 24 months in the reference cohort (n = 36), 16 additional fractures were observed in 12 individuals. 67% of all fractures occurred at an uninvolved bone in both groups.

In conclusion, men with mCRPC, especially those receiving radium-223, are at risk of fracture and should be treated with a bone health agent to lower the chance of fragility fractures.

Reference:

Hijab, A., Curcean, S., Tunariu, N., Tovey, H., Alonzi, R., Staffurth, J., Blackledge, M., Padhani, A., Tree, A., Stidwill, H., Finch, J., Chatfield, P., Perry, S., Mu Koh, D., Hall, E., & Parker, C. (2021). Fracture Risk in Men with Metastatic Prostate Cancer Treated With Radium-223. In Clinical Genitourinary Cancer (Vol. 19, Issue 5, pp. e299–e305). Elsevier BV. https://doi.org/10.1016/j.clgc.2021.03.020