What is osteosarcoma?

Osteosarcoma is a type of sarcoma. Sarcomas are rare cancers that develop in the supporting tissues of the body. Supporting tissues include bone, cartilage, tendons, fat and muscle.

There are 2 main types of sarcoma:

Bone sarcomas can develop in any bone in the body. They can also develop in the soft tissue near bones.

Osteosarcoma is a type of bone sarcoma that usually develops in growing bones. It is most often found in teenagers and young adults. But it can happen at any age. About 1 in 10 osteosarcomas (10%) develop in adults in their 60s and 70s. It is slightly more common in men than women.

Osteosarcoma can affect any bone. But the most common areas are the arms or legs (often near the knee joint).

Types of osteosarcoma

There are different types of osteosarcoma. These are named depending on where the cancer starts in the bone, for example inside the middle of the bone, or on the surface of the bone. It also includes the grade of the cancer.

The most common type of osteosarcoma is called conventional osteosarcoma. It is found inside the middle of the bone. Subgroups of conventional osteosarcomas include:

  • osteoblastic
  • fibroblastic
  • chondroblastic.

There are also rarer types of osteosarcoma. These include:

  • parosteal
  • periosteal
  • telangiectatic
  • small cell osteosarcoma.

Your cancer doctor or specialist nurse can tell you more about the type of sarcoma you have.

Symptoms of osteosarcoma

Pain is the most common symptom of bone cancer. But symptoms may vary, depending on where the cancer is. There may be some swelling in the area, and it may be painful to touch.

Primary bone cancer is sometimes found when a bone that has been weakened by cancer breaks. This could be after a minor fall or accident.

These symptoms can be caused by other conditions that are more common than bone cancer. If you have any swelling or unexplained bone pain, get it checked by your GP.

Tell your GP if the pain happens at night and when you are resting.

Causes of osteosarcoma

The exact causes of primary bone cancer are not known. The development of osteosarcoma may be related to when the bones are growing quickly, such as during puberty. This could explain why osteosarcoma is more common in teenagers.

Adults with a bone condition called Paget’s disease or who have had radiotherapy in the past may have a slightly higher risk of developing osteosarcoma later in life.

Rarely, osteosarcoma may occur in people from families where there is an inherited faulty gene (Li-Fraumeni syndrome). This gene change increases the risk of developing other types of cancer.

Osteosarcoma diagnosis

Tests and diagnosis

You may have some of the following tests to diagnose osteosarcoma:

  • Bone x-ray

    You may have an x-ray to check an area of bone for cancer. An x-ray shows a picture of the bone. This can give information about where the cancer may have started or what type of bone cancer it is.

  • MRI scan

    An MRI scan uses magnetism to build up a detailed picture of areas of your body.

  • Bone biopsy

    A bone biopsy means the doctor takes a sample of cells from the bone to be checked for cancer under the microscope.

Tests to diagnose bone cancer such as, bone biopsies, are done by a specialist team. We have more information about diagnosing bone cancer that explains more about these and other tests for bone cancer.

Waiting for test results can be a difficult time, we have more information that can help.

Staging and grading

The results of your tests give your cancer specialist information about:

  • the grade of the cancer – how the cancer cells look under the microscope. This gives an idea of how quickly a cancer may grow and develop.
    • Low-grade means the cancer cells look like normal bone cells. They are usually slow-growing and less likely to spread. Most chondrosarcomas are low-grade.
    • High-grade means the cancer cells look very abnormal. The cells are likely to grow more quickly and are more likely to spread.
    • Higher-grade chondrosarcomas are more likely to come back (recur) and may spread to other parts of the body.

    Most osteosarcomas are high-grade. But there are some rarer sub-types, which are usually low-grade.

    • the stage of the cancer - its size and whether it has spread outside the bone.

    We have more information about staging and grading bone cancer. Your cancer doctor or specialist nurse will explain how it may help plan your treatment.

Treatment of osteosarcoma

Osteosarcomas are rare, so they are treated by a team of doctors and other healthcare professionals at a specialist hospital. This means you may have to travel to have treatment.

The type of treatment you have depends on:

  • the position and size of the cancer
  • if it has spread to other parts of the body
  • the grade of the cancer
  • your general health.

You usually have a combination of the treatments below for Ewing sarcoma. You may be offered some treatments as part of a clinical trial.

Your cancer doctor or specialist nurse will explain the treatment options to you:

  • Surgery

    Surgery is often used to remove an area of bone affected by osteosarcoma.

  • Chemotherapy

    Chemotherapy uses anti-cancer (cytotoxic) drugs to destroy cancer cells. Chemotherapy is an important treatment for most people with osteosarcoma. It is usually given before surgery for osteosarcoma. This is called neo-adjuvant chemotherapy. The aim is to treat the cancer in the bone and any cancer cells that may have broken away.

    You usually have more chemotherapy after surgery, to help destroy any remaining cancer cells. This is called adjuvant chemotherapy.

  • Mifamurtide (Mepact®)

    Children, teenagers and young adults (aged 30 or under) having adjuvant chemotherapy may also have a drug called mifamurtide (Mepact®). This can help reduce the risk of osteosarcoma coming back. Your cancer doctor can give you more information about this.

  • Radiotherapy

    Radiotherapy treats cancer by using high-energy rays to destroy the cancer cells. Radiotherapy is not often used to treat osteosarcoma. It may be used when surgery is not possible.

After osteosarcoma treatment


After you finish your treatment, you will have regular check-ups and x-rays. These will continue for a few years. Tell your cancer doctor as soon as possible if you have any problems, or notice any new symptoms in between your regular follow-up appointments.

Possible late side effects

A small number of people may develop late side effects from the treatment, sometimes many years later. Late effects may include:

If treatment involves removing bones and muscle, you may find day-to-day tasks hard. How hard you find things will depend on where in the body the cancer started. It will also depend on whether you had limb-sparing surgery or an amputation.

Your cancer doctor or specialist nurse will explain more about any possible late side effects.

Getting support

You may have many different emotions, including feeling angry, sad, and scared. You may cry a lot or you might find it hard to relax. You may have problems sleeping. These are normal reactions, but they can be hard to cope with. It is important to remember there is lots of support to help you.

How much support you need is different for everyone. It may depend on the treatment and any side effects you have. Your cancer doctor will tell you about any possible side effects and how to deal with them before you start treatment.

We have more information about coping with difficult feelings and the support available. You may also find the following organisations helpful.

Organisations such as Sarcoma UK and Bone Cancer Research Trust can provide information and support. Cancer52 represents many charities and works to improve the quality of life for people with rarer types of cancer.

Macmillan is also here to support you. If you would like to talk, you can:

Reviewed: 31 March 2019
Reviewed: 31/03/2019
Next review: 30 September 2021
Next review: 30/09/2021

This content is currently being reviewed. New information will be coming soon.