Radiation therapy may be used for pain relief rather than as treatment for primary cancer in patients with cancer that has spread to the bone. Radiation may be given as local therapy directly to the tumor or to larger areas of the body. Local or whole-body radiation therapy may make pain medication and other noninvasive therapies work better by directly affecting the cause of the pain (for example, by shrinking tumor size). Radiation therapy may help patients with bone pain from cancer to move more freely with less pain.
Pain flare is an increase in pain after radiation therapy that develops before pain is relieved. Pain flare is being studied in patients receiving radiation therapy for cancer that has spread to the bone.
External-beam radiation therapy (EBRT) is a type of radiation therapy that uses a machine to aim high-energy x-rays at the cancer from outside the body. EBRT relieves pain from cancer that has spread to the bone in many patients. Radiation therapy may be given in a single dose or divided into several smaller doses given over a period of time. Single dose schedules and multiple dose schedules of EBRT are both effective for pain relief but single dose therapy is more likely to need to be repeated. Single dose EBRT for pain relief has not been found to cause more long-term harm than multiple dose EBRT. The decision whether to have single or multiple dose EBRT may also depend on how convenient the treatments are and how much they cost.
Stereotactic body radiation therapy (SBRT) is a type of external radiation therapy that uses special equipment to position a patient and precisely deliver radiation to tumors in the body (except the brain). This type of radiation therapy helps spare normal tissue. SBRT may be used to treat cancer that has spread to the bone, especially spinal tumors. SBRT may also be used to treat areas that have already received radiation.
The use of radiation therapy given together with bisphosphonates is being studied in patients with cancer that has spread to the bone. More studies are needed to find out if giving bisphosphonates with radiation therapy relieves pain better than radiation therapy alone.
Radiopharmaceuticals are drugs that contain a radioactive substance that may be used to diagnose or treat disease, including cancer. Radiopharmaceuticals may also be used to relieve pain from cancer that has spread to the bone. A single dose of a radioactive agent injected into a vein may relieve pain when cancer has spread to several areas of bone and/or when there are too many areas to treat with EBRT. Small areas of cancer may respond to radiopharmaceuticals while large areas usually do not. A second treatment may be helpful in patients whose pain does not respond to a single treatment. One study showed that more than 2 doses of a radioactive substance called samarium 153 may be safe and effective in patients who responded to their first dose. Radiopharmaceuticals have not been shown to prevent the need for EBRT in relieving pain from cancer that has spread to the bone.
Radiofrequency ablation uses a needle electrode to heat tumors and destroy them. An imaging method is used to insert the electrode through the skin and guide the needle to the right location. This procedure may relieve pain in patients who have cancer that has spread to the bone. More study is needed to learn about possible risks and benefits.