How does radiation relieve pain in bone cancer patients? once an area is treated, will pain later reoccur in that location, or will it stay pain free?

Kills tumor: Radiation is more deadly to cancer cells than non-cancer cells because they are dividing more readily and probably even more so because their genome is destabilized and they tend to lose the ability to repair radiation damage. Normal bone replaces the dead tissue; if the cancer does not recur there the site should remain pain-free. Depends on the type of cancer. Good luck.

Tumors can: Destroy the internal "marrow spaces" and even the hard surfaces. Bones have an innervated periosteum, sac around the bone, and it is the sretching that causes pain. Radiation is used to kill the cancer, and allow normal healing of a fracture caused by the tumor. It usually is sufficient. Sometimes internal fixation (an operation) may be part of treatment.