Primary bone cancer is cancer that starts in the bone, rather than starting in another part of the body and then spreading to the bone. The latter is known as secondary bone cancer. Unlike primary bone cancer, secondary bone cancer is common in cases of advanced cancer.
Bone pain is the most common symptom of primary bone cancer.
How common is bone cancer?
Primary bone cancer is a rare type of cancer that accounts for just one in every 500 cases of cancer in the UK each year. There are an estimated 500 cases every year. The cause of most cases of bone cancer is unknown.
Types of primary bone cancer
The four most common types of primary bone cancer are:
- osteosarcoma,
- Ewing sarcoma,
- chondrosarcoma, and
- spindle cell sarcoma.
The different types are described below
Osteosarcoma
Osteosarcoma is the most common type of bone cancer, with an estimated 150 cases a year in the UK. Most cases of osterosarcoma develop in children and young people who are between 5-20 years of age, making it the third most common cancer in young people (after leukaemia and brain tumours).
Osteosarcoma usually develops in the larger bones, such as the thigh bone (femur) or the shin bone (tibia).
Ewing sarcoma
Each year, in the UK, there are an estimated 100 cases of Ewing sarcoma. As with osterosarcoma, Ewing sarcoma usually develops in children and young people who are between 10-20 years of age, although 10% of cases develop in people who are over 20 years of age.
Ewing sarcoma usually develops in the pelvis, thigh bone, or shin bone.
Chondrosarcoma
In the UK, there are an estimated 80 cases of chondrosarcoma each year. This type of bone cancer usually develops in adults who are between 40-50 years of age.
Chondrosarcoma begins in the cartilage cells before spreading to the bone. Cartilage is a tough, flexible tissue that lines the surface of many bones and joints.
The most common sites for chondrosarcoma to develop are:
- pelvis,
- thigh bone,
- upper arm bone (humerus),
- shoulder blade (scapula), and
- ribs.
Spindle cell sarcoma
There are an estimated 80 cases of spindle cell sarcoma every year. Spindle cell sarcoma is very similar to osterosarcoma in terms of its symptoms and treatment, except that it affects older adults who are aged 40 or over.
Rarer types of bone cancer
Rarer types of bone cancer include:
- chordoma - which is a type of cancer that starts in the base of the spine and usually affects men between 40-50 years of age, and
- angiosarcomas - which is a type of cancer than can start anywhere in the skeleton (sometimes in multiple sites at once) and usually affects adults who are 20 years of age or over.
Outlook
The most important factor in determining the likely outlook for cases of bone cancer is whether the cancer has spread from the bone to other parts of the body (metastasis).
The most common places in the body for the cancer to spread to are the lungs, and secondary lung cancer can be challenging to treat.
If bone cancer is diagnosed before it spreads out of the bone(s), the outlook is moderate to good because a cure is often achievable. This type of cancer is known as localised bone cancer.
Health professionals use a general measurement of a ‘five-year survival rate’ when describing cancer statistics. However, it should be stressed that the ‘five-year’ measurement is, in many senses, an arbitrary measurement and it does not mean that people with bone cancer only have a five year life expectancy.
For cases of localised bone cancer:
- between 55-70% of people with osterosarcoma will live for at least five years after receiving the diagnosis,
- about 70% of people with Ewing sarcoma will live for at least five years after receiving the diagnosis,
- about 80% of people with chondrosarcoma will live for at least five years after receiving the diagnosis, and
- about 60% of people with spindle cell sarcoma will live for at least five years after receiving the diagnosis.
If the bone cancer has spread to other parts of the body, the outlook is not as favourable because a cure is often not possible. This type of bone cancer is known as metastatic bone cancer.
For cases of metastatic bone cancer:
- about 30% of people with osterosarcoma will live for at least five years after receiving a diagnosis,
- about 30% of people with Ewing sarcoma will live for at least five years after receiving a diagnosis,
- between 10-30% of people with chondrosarcoma will live for at least five years after receiving a diagnosis, and
- about 25% of people with spindle cell sarcoma will live for at least fiver years after receiving a diagnosis.
Bone cancer is usually treated with a combination of chemotherapy, radiotherapy, and surgery.
