Bone health and metastatic breast cancer
Bone health is a concern to all of us as we age. But as a person living with metastatic breast cancer, you may have extra worries about bone pain, thinning breaks, or fractures, which can result from both cancer treatment and the spread of breast cancer to the bones.
Chemotherapy medicines and hormonal therapies, especially the aromatase inhibitors, can affect bone density. As you and your doctor discuss your treatment options for metastatic breast cancer, ask about possible bone complications and ways to lower your risk.
It may feel discouraging to have to worry about bone health along with everything else on your plate. But paying attention to your bone health will allow you to keep active.
Having tumors in your bone can cause the bone to become weak and break. Some women learn they have metastatic breast cancer in the bone, called bone metastases, when they experience new bone pain or fracture a bone and an x-ray shows the cancer.
Your risk for having bone problems because of your treatment for metastatic breast cancer depends on many factors. Most of those factors you have little control over. They include
- the type of treatment you are getting
- any past cancer treatment
- your age
- your menopausal status
- your ethnic background
- your family medical history and
- your personal overall health history
Common treatments to address bone problems in metastatic breast cancer are:
- Bisphosphonates strengthen and protect the bones and treat bone pain, or both. They can also lower levels of calcium in the blood, called hypercalcemia, if they are too high due to the tumor’s effect on the bone, the tumor itself or as a side effect of treatment. Two medicines approved for metastatic breast cancer are zoledronic acid (Zometa) and pamidronate (Aredia).
- Targeted therapies treat bone pain and lower the risk of bone complications, such as breaks and fractures. One medicine approved for metastatic breast cancer is denosumab (Xgeva), a RANK ligand inhibitor that works to prevent bone-related problems in people with bone metastasis.
- Supplemental calcium and vitamin D allow targeted therapies and bisphosphonates to work best
- Radiation therapy strengthens bone or treats pain from a tumor
- Strontium-89, a radioactive chemical given by IV, can treat bone pain
- Steroids treat pain and decrease swelling
- Surgery stabilizes a weak bone with a rod
Your providers will want to monitor you for some side effects you could have with bisphosphonates and denosumab. The one of greatest concern to most women is osteonecrosis of the jaw, or exposed bone in the jaw that does not heal. All bisphosphonate treatment can cause ONJ, but your risk for it is higher when you take bisphosphonates for a long time for metastatic disease. Before you start taking a bisphosphonate, see your dentist. During your treatment, make sure you speak with your oncology team if you need any invasive dental work done, such as a tooth extraction.
Bisphosphonates can also cause kidney problems, which in rare cases leads to kidney failure. To check for problems, your providers will monitor the creatinine level in your blood. Healthy kidneys filter creatinine, a waste product, from your blood. If your kidneys aren’t working as well as they should, your blood will have a higher level of creatinine.
Your doctor will be able to tell you about the pros and cons of these treatment options and what follow-up monitoring may be needed required.
There are also some nonmedical steps you can take to reduce your risk for bone fractures. Among them:
- Weight-bearing exercise. Even a short, brisk walk each day will help keep your bones strong. Dancing, low-impact aerobics and racquet sports are also good.
- Strength-training exercise. Exercising with free weights, resistance bands or in a swimming pool can help improve strength. Be sure to check with your doctor before starting a new form of exercise.
- Nutrition. A well-balanced diet with sufficient calcium and vitamin D promotes good bone heath. Talk to your doctor if you are considering taking supplements.
- Avoid smoking and limit alcohol, as both can lead to bone loss.