Understanding Bone Metastasis
Local treatments focus on treating one or a few bone metastases.
External radiation therapy
This type of treatment uses high-energy rays or particles to destroy cancer cells or slow their rate of growth. When a cancer has spread to a small number of spots in bones, radiation can be used to help relieve symptoms such as pain. The most common way to give radiation for a bone metastasis is to focus a beam of radiation from a machine outside the body. This is known as external beam radiation.
If a bone is so weak that there is a risk of a bone fracture, radiation is not likely to help. Instead the bone must be stabilized with surgery (see below). But if the bone is treated with radiation before it gets too weak, it may be able to help prevent a later fracture.
Radiation therapy for bone metastasis can be given as 1 or 2 large doses or in smaller amounts over 5 to 10 treatments that result in a somewhat larger total dose. Most radiation oncologists (doctors who specialize in radiation therapy) prefer to give radiation over several sessions. Both give the same degree of pain relief. The advantages of the 1- or 2-dose treatment include fewer trips for treatment and lower costs. The advantage of more treatments is that patients are less likely to need re-treatment because of the pain coming back.
External radiation therapy is much like getting an x-ray, but the radiation is more intense. To reduce the risk of side effects, doctors figure out the exact dose and aim the beam carefully to hit the target. The procedure itself is painless. Each actual treatment lasts only a few minutes, although the setup time – getting you into place for treatment – usually takes longer.
External beam radiation might be a good option if you have 1 or 2 bone metastases that are causing symptoms. But if you have many metastases scattered throughout your bones, treatment with a radiopharmaceutical is more likely to be helpful.
If you would like more information about radiation therapy, ask for our document called Understanding Radiation Therapy: A Guide for Patients and Families.
Putting a needle or probe directly into a tumor and using heat, cold, or a chemical to destroy it is called ablation. It may be used if only 1 or 2 bone tumors are causing problems.
A common type of ablation, radiofrequency ablation (RFA) uses a needle that carries an electric current. The tip of the needle is put into the bone tumor. CT scans may be used to be sure the needle is in the right place. Electric current delivered through the needle heats the tumor to destroy it. RFA is usually done while the patient is under general anesthesia (deeply asleep and not able to feel pain).
In another type of ablation, called cryoablation, a very cold probe is put into the tumor to freeze it, killing the cancer cells. Other methods use heat (laser-induced interstitial thermotherapy) or alcohol to kill the cells. After the cancer tissue is destroyed, the space left behind may be filled with a bone cement (discussed below).
Although surgery to remove a primary bone tumor (one that started in the bone) is often done to try and cure the cancer, the purpose of surgically treating a bone metastasis is to relieve symptoms and/or stabilize the bone. Bone metastases can weaken bones, leading to breaks (fractures) that tend to heal very poorly. An operation can be done to place screws, rods, pins, plates, cages or other devices to stabilize the bone and help prevent fractures. If the bone is already broken, surgery can often relieve pain quickly and help the patient return to their usual activities.
Sometimes a person can't have surgery because of their poor general health, other complications of the cancer, or side effects of other treatments. If doctors can't surgically reinforce a bone that has metastasis, a cast or splint may help stabilize it to reduce pain so the person can move around.
Another option to strengthen and stabilize a bone is to use injections of a quick-setting bone cement or glue called polymethyl methacrylate (PMMA). When PMMA is injected into a spinal bone it's called vertebroplasty or kyphoplasty. This helps stabilize the bone and relieves pain in most people. When the bone cement is injected to strengthen bones other than the spine, it is called cementoplasty. Sometimes, it is used along with surgery, radiation, radiofrequency ablation, or other treatments, depending on the person's medical situation. A person with spinal cord compression, an infection, or in poor health might not do well with this treatment.
Last Medical Review: 05/03/2012
Last Revised: 05/03/2012