Cancers that start in one part of the body can spread to other parts of the body. If a tumor has spread to the bone, this new cancer site is called a bone metastasis. In most cases, bone metastases are the result of the original spread of cancer cells to the bone. For example, a person with breast cancer will often metastasize to the bone.

If prostate cancer has metastasized, bone is often the first place. Therefore, when cancer has spread beyond the prostate, the goal of treatment will be to prevent or slow metastasis to the bone. In case it has really metastasized to the bone, it is necessary to relieve pain and control other complications.