Metastatic breast cancer is breast cancer that has spread beyond the breast and nearby lymph nodes to other parts of the body (most often the bones, lungs, liver or brain).
Metastatic breast cancer is not a specific type of breast cancer, but rather the most advanced stage of breast cancer. It’s also called is also called stage IV or advanced breast cancer.
For some people, metastatic breast cancer only spreads to one part of the body. For other people, the cancer spreads to multiple parts of the body over time. For others, the cancer is found in multiple parts of the body when they are first diagnosed.
Learn about treatment for metastatic breast cancer.
One of the most common sites of breast cancer metastases is the bones. When metastatic breast cancer spreads to the bones, it’s called bone metastases.
Bone metastases are not bone cancers. Although the cancer is in the bones, it’s still breast cancer. It’s treated with breast cancer therapies, not bone cancer therapies.
Bone metastases may be present when metastatic breast cancer is first diagnosed, or the cancer may spread to the bones at a later time.
The bones are the first site of metastases for almost half of women diagnosed with metastatic breast cancer . For many of these women, the bones will be the only site of metastases .
For people with estrogen receptor-positive metastatic breast cancer, the bones are the most common site of metastases.
For people with estrogen receptor-negative metastatic breast cancer, the lungs and liver are the most common sites of metastases.
As treatment for metastatic breast cancer improves, so does survival. With people living longer with metastatic breast cancer, preventing and treating any side effects of bone metastases is very important. Side effects can greatly impact quality of life.
People with bone metastases are at risk of serious bone complications such as bone fractures (breaks), spinal cord compression and bone pain. Bone complications are sometimes called skeletal-related events (SREs).
Bone complications are common with bone metastases. Up to 70 percent of people with metastatic breast cancer and bone metastases will have one or more bone complication within the first 2 years of diagnosis .
Bone problems can cause pain and may lead to loss of mobility, impacting quality of life. They can also decrease survival .
Bone metastases can damage your bones. Medications to strengthen and protect your bones (bone-strengthening drugs) reduce this damage and have greatly improved the treatment of bone metastases.
There are 2 types of bone-strengthening drugs:
Thanks to the regular use of these drugs, it’s now rare for people with bone metastases to be hospitalized for bone complications or hypercalcemia (high levels of calcium in the blood that can weaken bones, cause kidney stones and can lead to heart problems).
If you have bone metastases, your treatment plan will include a bisphosphonate or denosumab. Talk with your doctor about which drug is right for you.
For people with bone metastases, the use of bisphosphonates or denosumab can :
Learn about bisphosphonates in early breast cancer treatment.
In some people, bisphosphonates and denosumab can cause joint or muscle pain [43-44]. Although they are used to treat bone pain, they can also cause bone pain [43-44]. These types of pain usually only last for a day or two, and only with the first treatment.
In rare cases, with either bisphosphonates or denosumab, a disorder called osteonecrosis of the jaw may occur [43-44]. To reduce the risk of this disorder, have a dental exam and take care of any dental work before starting treatment with bisphosphonates or denosumab .
Talk with your oncologist before getting any dental work while you’re on bone-strengthening therapy.
Bone-strengthening drugs can reduce pain from bone metastases, but they shouldn’t be the only treatment for bone pain . Bone pain should also be treated with standard pain management methods.
Bone pain often responds to heat, or to mild pain relievers such as ibuprofen (Advil or Motrin), naproxen (Aleve or Naprosyn) or acetaminophen (Tylenol).
Although you can get these medications without a prescription, check with your health care provider before taking them. For example, if you have (or are expected to have) a low blood count, your kidneys are not functioning normally, or you have heart failure, your provider may advise you not to take ibuprofen or naproxen.
Learn more about these medications in metastatic breast cancer care.
Tramadol or opioids (such as morphine or oxycodone) can be added if the ibuprofen, naproxen or acetaminophen alone don't relieve the pain.
All of these drugs can cause constipation, so you may need to make some changes in your diet or take medications to promote regularity. For example, your provider may recommend eating high-fiber foods and drinking plenty of liquids (warm or hot liquids may be helpful) to manage constipation.
Other side effects of these drugs include sleepiness and nausea. These usually go away after about a week. If they don’t go away, tell your provider. These side effects can be treated.
If you’re prescribed opioid medications, your provider will carefully monitor the amount prescribed so you don't take too much. People may worry about taking opioid medications, fearing side effects or addiction. However, when used as prescribed, these drugs can offer a great deal of pain relief and will not cause addiction.
Learn more about opioids and other pain medications, their side effects and fear of addition.
Radiation therapy to the bone can relieve pain at the site of the tumor(s) and prevent fractures.
Drugs called radiopharmaceuticals (samarium (Quadramet) or alpharadin (Xofigo)) can also treat pain from bone metastases. If you are likely to benefit from this therapy, your oncologist can refer you to a doctor who specializes in nuclear medicine.
Surgery may be used to prevent or repair bone fractures.
Chemotherapy or hormone therapy can relieve bone pain by shrinking the cancer so it doesn’t press upon the spine or other bones .
Learn more about managing pain related to metastatic breast cancer.
Facts for Life: Bone Protection for People with MBC
Questions to Ask Your Doctor: Bone Protection
Risk and Prevention of Bone Complications
Metastatic Breast Cancer Progress
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