Have other patients been treated with skeletal targeted radiotherapy?

Sarcomas. It could possibly be used with any tumor localized to bone, trials on multiple myeloma have been done, it has also been considered as treatment for ewing's sarcomas and osteosarcoma.
Mostly used in. Prostate cancer, strontium has been used for more than 20 years, now radium is touted for survival prolongation. It can impair marrow, so many medical oncologist use as last resort, and it is administered in nuclear medicine departments. Ask a radiation oncologist for advice.