Usually the prostate cancer
patients will have long survival even with bone mets comparing to other cancers.The tumor
burden in the body will be known by Serum PSA levels. Giving radiation
to whole bones may cause decreasing of his blood cells , due to bone marrow
exposure, this will in turn causes infections. the crucial point at this juncture is how can we control his infections.The age and situation you mentioned is causing alarm but in the cancer patients, anything can happened at any time. we should be positive always.