More Radium 223 vs EBRT questions

[baltha]

Though this quote is from an old Vogelzang article, it does not seem contradicted by newer studies:

"Both EBRT and radium-223 are effective at relieving pain, but both may decrease bone marrow function. Since radium-223 has a documented survival advantage compared with the standard of care, which includes as-needed EBRT, the data favor radium-223 over EBRT for painful bone metastases."

Questions remain in my confused brain:

Which of the two therapies leaves a treated bone more thoroughly free of active malignancy?

Which therapy leaves this same bone free of malignancy for a longer time?

Which of the two therapies leaves the same treated bone in a stronger condition?

Which of the two therapies has the fewest serious risks, such as paralysis, promoting other cancers, etc ?

Grateful for your shared knowledge.

[Tall_Allen]

They are used in different situations. . Xofigo can stop progression in smaller loci than one can see on imaging. EBRT can only stop progression to larger loci where it is aimed. EBRT can only be used if there are few bone metastases and in safe places to irradiate. Xofigo can be used for very few or many bone metastases, and because it targets bone only, the "overspray" from EBRT is not an issue.

EBRT has no known effect on survival, whereas Xofigo does. They both may help with pain palliation. They both decrease fracture risk because it is the cancer that weakens the bone. However, when combined with a second-line hormonal agent, Xofigo increases the risk of fractures. This seems to be mostly, but not entirely mitigated by a bone-strengthening agent.

EBRT may provide excellent local control in a single dose if it is large enough. Xofigo is given once every 4 weeks for 6 injections. Some data suggest it can be repeated.

[Magnus1964]

EBRT is used for a single bone net, xofigo is used when bone mets are found in several places and cannot be irradiated by EBRT.