An osteosarcoma is a type of cancerous tumour that starts in the bone (called a primary bone cancer). It is more common in teenagers (more in young men) as it usually develops in growing bones.
- Osteosarcomas are commonly found in the knee, the hip, the shoulder and the long bones of the legs.
- The tumour is mostly found in the centre of the bone.
What Causes Osteosarcoma?
The causes of osteosarcoma is unknown, however it is suggested that is could be caused by rapid bone growth. This may be why it is often found in teenagers.
There are some links between having previous radiotherapy for other forms of cancer and developing an osteosarcoma.
What are the symptoms?
- Pain is the most common symptom of osteosarcoma. This depends on where the cancer is located.
- There may be some swelling over the site, or it may be sore to touch.
- Sometimes because the bone is weakened from the cancer, it can break easily. This is sometimes how people find out about their cancer.
TIP: The symptoms described could be related to many things. However if you have ongoing bone pain, especially at night, then you should get checked by your doctor.
How is it Diagnosed?
After visiting a GP a referral with most probably be made to a hospital for some tests. These may include:
- Bone scan
- Blood test
- Bone marrow aspirate
- CT scan
If the results of the test show osteosarcoma, another referral will be made to a doctor who specialises in the treatment of bones (called an orthopaedic doctor).
Some of the tests will be done by a specialist bone surgeon.
Once the cancer is diagnosed, it will be graded. This means that cells will be looked at under a microscope and the rate in which they grow will be determined.
Cells that look mostly normal (and are slow-growing) are given a lower grade than cells that look abnormal which are high-grade (and are fast-growing).
Most osteosarcomas are high-grade.
Osteosarcomas are staged according to their size and whether they have spread from their primary location. Staging is used to help doctors work out a treatment plan.
- Stage 1A: Low-grade and is contained within the bone.
- Stage 1B: Low-grade cancer found outside the bone.
- Stage 2A: High-grade and is contained within the hard coating of the bone.
- Stage 2B: High-grade cancer extending outside the bone and into the soft tissue spaces. Most osteosarcomas are stage 2B.
- Stage 3: The cancer can be low-grade or high-grade and it is found either within the bone or outside it. The cancer has metastasised and spread to other parts of the body.
How is it Treated?
A team of doctors and other staff at the hospital will plan the treatment. It will depend on the grading and staging of the tumour.
Treatment may be coordinated by an oncologist (a doctor who specialises in treating cancer with chemotherapy) an orthopaedic surgeon (a surgeon who specialises in bones) and a radiologist (a doctor who specialises in treating cancer with radiation).
Treatment may involve:
Most people have chemotherapy to shrink to size of the tumour and to get rid of any cancer cells around the body. This is usually followed with surgery to remove the tumour. More chemotherapy and sometimes radiotherapy usually follows.
Chemotherapy for osteosarcoma
- This treatment is often given to people with osteosarcoma to shrink the tumour prior to surgery. This means that the surgery will be less invasive.
- Often chemo starts again after surgery to kill any remaining cancer cells and stop them from spreading. This is called adjuvant chemotherapy (after surgery).
For more information, go to our chemotherapy fact sheet.
Surgery for osteosarcoma
- The aim of surgery is to remove the tumour. Because of the type of tumour (being in the bone) it can often be difficult to remove. Sometimes some of the bone will be removed, and either a prosthesis (a metal replacement bone), or a bone graft (bone taken from another part of the body) will be inserted. This is known as limb-sparing surgery.
- Unfortunately because of the location of the tumour, sometimes limb-sparing surgery doesn’t work and a limb might have to be amputated. It only ever happens if it is completely unavoidable. This is because the cancer has spread from the bone and into the nearby blood vessels.
For more information, go to our surgery fact sheet.
Radiotherapy for osteosarcoma
Osteosarcomas are not very sensitive to radiotherapy, so it’s often not used as a treatment. However, it can be given after surgery to destroy remaining cells, or if there is a risk of the cancer spreading to other tissues.
For more information, go to our radiotherapy fact sheet.