Bone Metastasis

What is bone metastasis?

Bone metastasis is a symptom of metastatic cancer that happens when cancer from one place in your body spreads to your bones. It typically affects people with breast cancer, lung cancer and prostate cancer, but other types of cancer can also cause bone metastasis. There’s no cure for this condition, but there are treatments to ease symptoms and keep it from getting worse.

Bone metastasis is increasingly common in part because people are living longer with cancer. For example, one analysis showed the incidence of bone metastasis increased every year, from 3% in the first year after diagnosis to 8% within 10 years after diagnosis.

What are the symptoms of bone metastasis?

The most common symptom is bone pain, which can feel like a dull ache that gets worse at night or a sudden sharp pain. Bone metastasis can cause complications with specific symptoms:

• Bone fractures: Bone metastasis makes your bones more fragile and likely to break even if you don’t fall. The condition can affect any bone in your body, but often affects your spine and ribs, pelvis, upper arm bone (humerus), upper leg bone (femur) and skull. Bone fractures cause sharp, severe pain. If you break your leg or arm, you won’t be able to move it.
• Hypercalcemia: This is high calcium levels in your blood. Hypercalcemia symptoms include confusion, constipation, loss of appetite, nausea and vomiting.
• Spinal cord compression: A metastatic tumor pressing on your spinal cord may cause back pain, weakness or numbness in your arms and legs, and affect your ability to control when you pee (urinary incontinence).

What causes bone metastasis?

This condition happens when cells from cancerous tumors enter your blood and travel to your bones. Once there, the cancerous cells set off what experts call the vicious cycle of bone metastasis.

To understand the cycle, it may help to know more about how your bone cells work. There are two types of bone cells — osteoblasts and osteoclasts. Osteoblasts build new bone cells, while osteoclasts dissolve and break down old or damaged bone cells.

Normally, these two bone cell types work together to keep a constant flow of new bone cells taking the place of old bone cells. Cancer in your bones disrupts that process. Here’s how that happens:

• When osteoblasts make too many new bone cells, your bone builds up and has abnormal areas of bone formation. Your provider may call these areas osteosclerotic or osteoblastic lesions. These areas are hard, but they’re fragile, like thin ice near a frozen riverbank, which is easy to break through or collapse.
• When osteoclasts break down bone cells faster than usual, the substances that your bone cells release create tiny holes in your bone. Viewed under a microscope, your bone may look like something punched holes in it. Your provider may call these holes osteolytic lesions. The lesions make your bone more fragile and weaker, increasing the risk you’ll break a bone.

Research shows links between bone cell types and specific types of metastatic cancer. For example, 70% to 85% of bone metastasis from prostate cancer is osteogenic, meaning it happens when osteoblasts make too many bone cells. But 75% of metastatic breast cancer is osteolytic from bone cells that break down too fast.

How is bone metastasis diagnosed?

Your healthcare provider will do several imaging tests to diagnose the condition. They may do blood tests or urine tests to look for substances that are signs of bone damage. Imaging tests may include:

• Bone scan.
• Computed tomography (CT) scan.
• Magnetic resonance imaging (MRI) scan.
• Positron emission tomography (PET) scan.
• X-ray.

What are the treatments for bone metastasis?

Healthcare providers can’t cure bone metastasis, but they can provide medication and procedures to help with bone metastasis pain and keep the condition from getting worse. Specific treatments may include:

• Bisphosphonates: Pamidronate and zoledronic acid (Zometa®) strengthen your bones and reduce the amount of calcium in your blood and your risk of developing hypercalcemia.
• Chemotherapy or hormone therapy: Your provider may order one of these if you have bone metastases (more than one cancerous tumor in your bone (s).
• Monoclonal antibody therapy: They may prescribe denosumab (Prolia® or Xgeva®) to reduce the risk you’ll break a bone.
• Radiation therapy: Your provider may order radiation therapy for pain from a single tumor in your bone. This treatment helps with pain from spinal cord compression. Your provider may combine radiation therapy with corticosteroids.
• Kyphoplasty: This procedure treats spinal compression fractures.
• Surgery: Your provider may recommend surgery to reinforce fragile bones or to remove a tumor.

What happens if I don’t receive treatment?

Bone metastasis causes complications like hypercalcemia, which can lead to coma if you don’t receive treatment. Without treatment, you may have bone fractures that affect your ability to walk or take care of yourself. You may have severe bone pain that can affect your quality of life. You also run the risk of having spine compression which may lead to paralysis.

What can I expect if I have bone metastasis?

If you have bone metastasis, it means you have cancer somewhere else in your body that’s spread to your bones. Bone metastasis is a sign of advanced cancer. If this is your situation, you’ll need medical care and support for the primary cancer and bone metastasis.

How long can you live with bone metastasis?

Survival rates range from six to seven months to more than four years, and vary based on factors like:

• Cancer type: One analysis states the survival rate for lung cancer to bone is six to seven months, compared to 53 months for prostate cancer to bone.
• Cancer stage: People with Stage I cancer at diagnosis were much less likely to develop bone metastasis than people with Stage IV cancer at diagnosis. Specifically, researchers who tracked bone metastasis rates 10 years after cancer diagnosis found that 3% of people with Stage I cancer had bone metastasis, compared with 28% of people with Stage IV cancer.

I had Stage I cancer that went into remission. Why did my cancer spread?

Unfortunately, there are situations where you can develop metastatic cancer, including bone metastasis, after cancer treatment puts the condition into remission. Remission means you don’t have symptoms and tests don’t find signs of cancer. If you have bone metastasis, your healthcare provider may refer to your condition as distant recurrent cancer. Recurrent cancer is when cancer comes back after treatment.

How do I take care of myself?

Bone metastasis can affect your quality of life, from dealing with symptoms like pain to coping with the realization that cancer is spreading. Here are some suggestions that may be helpful:

• Eat well: Bone metastasis may cause complications that affect your appetite. Talk to a nutritionist about healthy eating plans.
• Consider cancer survivorship programs: You’re a cancer survivor the day you receive a diagnosis, and you’re a survivor now as you deal with bone metastasis. There may be programs or support groups for people in your situation.
• Ask about palliative care: Often, bone pain is the first symptom of bone metastasis. Pain from bone metastasis can be severe and affect your quality of life. In palliative care, you’ll receive pain medication and other pain management support. Other palliative care services include psychological counseling to help you manage mental health issues that can develop when you have incurable cancer.
• Explore clinical trials: Researchers are evaluating new ways to treat bone metastasis in different kinds of cancer. Ask your healthcare provider about clinical trials that may be appropriate for you to consider.

Should I consider hospice care?

That depends on your situation. Your provider may recommend hospice care if continuing cancer treatment isn’t likely to result in a cure and they believe your life expectancy is six months or less once you stop treatment. Hospice care emphasizes your physical comfort, keeping you free of pain and managing other symptoms.

When should I see my healthcare provider?

Contact your provider if you have bone metastasis symptoms that are getting worse, like pain that you can’t control with medication as prescribed by your provider. It’s important to remember that you don’t need to live with the severe pain that bone metastasis can cause. Your provider will prescribe medication and other treatments that ease pain without affecting your quality of life, like your ability to interact with those you love.

When should I go to the emergency room?

Call 911 or go to the emergency room right away if you have symptoms of spinal cord compression like:

• Your legs, feet or lower belly feel tingly or numb.
• You have trouble moving your legs.
• You can’t control when you pee or poop.
• You can’t pee.

Spinal cord compression that isn’t treated may lead to paralysis.

What questions should I ask my healthcare provider?

A bone metastasis diagnosis can affect your quality of life at a time when you’re already dealing with cancer. Here are some suggestions for questions you may want to ask:

• Which bone or bones now have cancerous cells?
• What does having bone cancer mean in terms of my overall prognosis?
• What are the treatments or combinations of treatments that may help me?
• Will treatment keep bone metastasis from spreading to other bones?
• What are my options for managing bone pain?
• How do I reduce my risk of bone fractures?

What’s the difference between bone cancer and bone metastasis?

Bone cancer is cancer that starts in your bones, like osteosarcoma or Ewing sarcoma. Bone metastasis is cancer that starts in another part of your body and then spreads to your bones.