Bone metastasis occurs when cancer cells from other parts of the body spread to the bone. The most common area for bone metastasis is the spine. The first symptom a person might experience is bone pain.
Bone metastasis not the same as bone cancer. Bone cancer begins in the bone instead of developing due to cancer cells spreading from other parts of the body.
This article will look at what bone metastasis is and its treatment options. It will also discuss symptoms and diagnosis.
Bone metastasis occurs when cancer cells break free from the original tumor and travel through the bloodstream. Cancer cells in the bloodstream can then reach other parts of the body.
Although the immune system will attack these cancer cells, some may survive and begin to grow in another part of the body.
Other types of cancer that commonly lead to bone metastasis include:
- bladder cancer
- kidney cancer
- thyroid cancer
According to the American Cancer Society, the most common sites for bone metastasis are the:
- upper leg bone, or femur
- upper arm bone, or humerus
There are two different types of bone metastasis: osteolytic and osteoblastic.
People can have both osteolytic and osteoblastic metastasis. The following sections will look at these in more detail.
Osteolytic metastasis develops when cancer cells break down the bone and weaken it. Cancer cells can destroy parts of the bone and form holes.
The Canadian Cancer Society state that osteolytic metastases are more common than osteoblastic metastases and often occur with metastatic breast cancer.
Osteoblastic metastasis occurs when cancer cells spread to the bone and cause excess bone cells to form. This can make the bones very dense.
Osteoblastic metastases often occur with metastatic prostate cancer.
A healthcare team will create a treatment plan specific to each individual, depending on the type of cancer they have, its severity, and their medical history.
According to the Canadian Cancer Society, treatment for bone metastasis may include a combination of methods. The following sections will look at these in more detail.
To help relieve bone pain, a healthcare professional may prescribe:
- nonsteroidal anti-inflammatory drugs, such as ibuprofen
- opioids, such as morphine
- medications for nerve pain, such as pregabalin or gabapentin
Bisphosphonates can help slow the deterioration of the bones.
They can also help manage and prevent broken bones, bone pain, and hypercalcemia, which occurs when calcium levels in the blood are too high.
Side effects of these medications can include:
- flu-like symptoms
A healthcare professional may prescribe bisphosphonate medications alongside radiation therapy, pain medications, or chemotherapy.
Denosumab is a monoclonal antibody that attaches itself to RANKL, which is a protein. RANKL helps break down bones.
A healthcare professional may prescribe denosumab instead of bisphosphonate medications.
It is important to note that a person should visit a dentist before taking this medication. This is because it can affect the jaw.
Side effects of this medication can include:
- poor appetite
- diarrhea or constipation
- joint or muscle pain
This is a common treatment option for bone metastasis.
External radiation can treat bone pain and spinal cord compression. It may also help heal or prevent broken bones. External radiation refers to when a machine directs a beam of radiation through the skin to a specific area of the body.
Systematic radiation is another approach. This is an option if a person is experiencing bone pain in many locations across their body.
It is important to note that a person may experience a temporary increase in bone pain before it improves or disappears entirely.
Chemotherapy can help shrink bone metastases and relieve pain.
Chemotherapy drugs flow through the body and help destroy cancer cells. A person may undergo chemotherapy alongside radiation therapy and taking bisphosphonate medications.
Side effects of chemotherapy may include:
- bowel problems
- mouth problems
Hormonal therapy can help treat some types of cancer, such as prostate and breast cancer, that have spread to the bone.
It can help relieve bone pain and may have fewer side effects than chemotherapy.
Some side effects may include a loss of interest in sex and hot flashes.
Targeted therapy can help control the growth of bone metastases.
It finds and attaches itself to substances, such as proteins, on the cancer cells. These proteins send signals to tell the cells to divide and grow, but targeted therapy helps block these signals.
Side effects of targeted therapy can include flu-like symptoms and fatigue. However, a person can receive treatment for these side effects.
Immunotherapy can boost a person’s immune system. A person can take this treatment by itself or in conjunction with other treatment methods.
Side effects of immunotherapy can include fatigue and flu-like symptoms.
A person may need surgery to repair broken bones or help ensure that bones are more stable. A surgeon can place metal pins, screws, or rods for this purpose.
A healthcare professional may inject bone cement to help relieve pain from a broken bone. This approach can also help prevent bones from breaking.
Typically, a healthcare professional will use bone cement to treat the spine, arms, legs, and pelvis.
One 2020 article suggests that a local ablation can help those with persistent pain.
There are three types of local ablation:
- Radiofrequency ablation: This refers to when a healthcare professional uses a probe to apply an electrical current to a tumor.
- Cryoablation: This refers to when a healthcare professional inserts a thin needle through the skin and into the tumor to freeze the tissue.
- Focused ultrasound: This uses ultrasonic energy to target the tumors.
The American Cancer Society note that one of the first symptoms of bone metastasis is often pain in the bone. Swelling may also be present.
For example, people may experience pain that:
- comes and goes in the beginning
- feels sharp or similar to a dull ache
- worsens at night
- improves with movement but later worsens with physical activity
- becomes constant over time
A person may also experience:
- unintentional weight loss
- difficulty breathing or shortness of breath
The sections below will look at some of the signs of bone metastasis.
Bone metastasis can weaken the bone, which can increase the risk of fractures. Fractures may occur during a fall or injury, but they can also occur through normal everyday activities.
If a person has a fracture, they may experience sudden and severe pain.
Common sites for fractures can include the long bones in the arms and legs, as well as the spine.
Bone metastasis can also cause hypercalcemia. This refers to when the bones release calcium into the bloodstream, causing high blood levels of calcium.
Some symptoms of hypercalcemia include:
- frequently needing to urinate
- feeling sleepy or sluggish
- constantly feeling thirsty despite drinking plenty of fluids
- muscle aches and weakness
- aching joints
- kidney failure
Spinal cord compression
If a person has bone metastasis in the spine, it can cause spinal cord compression.
To prevent paralysis, a person will need immediate treatment if they have spinal cord compression.
Symptoms of spinal cord compression can include:
- pain in the back, which may continue into one or both legs
- pain in the neck
- numbness in the stomach
- numbness or weakness in the legs
- loss of bladder or bowel control
Healthcare professionals may use radiation therapy, alongside steroid or corticosteroid medication, to treat spinal cord compression. They will begin treatment within 12–24 hours of diagnosis.
A healthcare professional will take a full medical history and perform a physical exam to look for swelling or areas of pain.
To diagnose bone metastasis, they may carry out certain tests. These include blood tests, to test bone marrow function and calcium levels, and imaging tests, such as X-rays, bone scans, CT scans, and MRI scans.
If a healthcare professional identifies bone metastasis before locating the primary cancer, they may carry out other tests to find the source of the cancer. These tests may include:
- a biopsy, wherein they will take a tissue sample
- mammography, which tests for breast cancer
- a chest X-ray or CT scan, to test for lung cancer
- a transrectal ultrasound, to test for prostate cancer
Bone metastasis is an advanced form of cancer, and it can be difficult to predict the outcome.
People can discuss any questions they have with a healthcare team, who can provide them with more information.
The American Academy of Orthopaedic Surgeons suggest that ongoing research and advances in medical treatments have resulted in significant improvement in the quality of life for people with bone metastasis.
Cancer that spreads can be difficult to control. However, treatments can help prevent or slow down the growth of cancer cells, as well as relieve the symptoms.
A person should contact a healthcare professional if they have any symptoms of bone metastasis.
If they have any symptoms of spinal cord compression, they will need immediate medical attention.
A person may want to find a local support group or network to connect with people going through similar experiences.
The National Cancer Institute provide more information on finding support here.
Some people may also find it helpful to talk with a mental health professional during this time.
People can also discuss the possibility of taking part in clinical trials, and the potential benefits and risks of doing so, with a healthcare professional.
Bone metastasis occurs when cancer cells from other parts of the body spread to the bone. The first symptom a person might notice is pain in their bones.
As bone metastasis is an advanced form of cancer, it can be difficult to predict the outcome. However, there are many treatment options available to help relieve the symptoms and slow down its development.
A person may want to seek additional support from a mental health professional or others going through similar experiences.