Bone cancer develops in the bones and joints and may spread to other organs including the lungs and liver. The treatment of bone cancer depends on the type of cancer and factors such as the patient’s age and the extent of the spread of cancer.
Here is an overview of the different forms of cancer that can affect the bones and joints.
What is bone cancer?
These bone cells are usually active. New bone cells are continually formed by osteoblasts to replace the old cells broken down by the osteoclasts.
The bones also consist of bone marrow. The marrow of some bones is formed of fatty tissue while in other bones, it is formed of a mixture of blood-forming cells and fat cells.
The blood-forming cells produce red cells, white cells, and platelets. Bone marrow also contains other cells like fibroblasts and plasma cells. 
Abnormal growth and multiplication of any of these cells in the bone or bone marrow can result in cancer. Depending on the cells involved, bone tumors and cancers can be of different types.
What are the different types of bone tumors?
Bone tumors can be benign or malignant. Benign tumors usually do not spread to other organs. Benign tumors are not known to cause life-threatening complications and can be treated with surgery.
The common types of benign tumors affecting the bones include:
- Osteoid osteoma
- Chondromyxoid fibroma.
Malignant bone tumors can spread to other organs of the body. They are called Sarcomas. They are categorized based on the bone affected and the types of cells forming the tumor.
Sarcomas can affect the tissues in the bones, muscles, fibrous tissues, fat tissue, and blood vessels. Sarcomas may also develop in other parts of the body. Here are some of the common malignant tumors that affect the bones.
Osteosarcoma, sometimes called osteogenic sarcoma, is the most common cancer affecting bone cells. It usually occurs in young patients between the ages of 10 and 40. In rare cases, it may affect patients over the age of 60. These tumors usually develop in the bones of the legs, arms, and pelvis. 
Chondrosarcoma begins in the cartilage cells. It is the second most common form of bone cancer. It is rare in people younger than 20. The risk of chondrosarcoma increases with age. It is more common in women than in men.  
Chondrosarcomas can start in the bones of the pelvis, arms, and legs. They may also affect the cartilage tissues in the larynx, trachea, scapula, skulls, ribs, and chest wall.
Chondrosarcomas are classified based on their grade or how fast they grow. The lower the grade of the tumor, the slower it grows. If a cancer is growing slowly, the risk of spread is lower.
This can improve the prognosis and enhance the patient’s chances of complete recovery. This highlights the importance of early detection of chondrosarcomas.
The different types of chondrosarcomas include clear cell chondrosarcomas, mesenchymal chondrosarcomas, and dedifferentiated chondrosarcomas.
3. Ewing tumor
Ewing tumor, also called Ewing sarcoma, is the third most common form of bone tumors. It is the second most common bone tumor affecting children and young adults.
In most cases, Ewing sarcoma develops in the bone tissues. It usually affects the long bones of the hands and legs. However, it may also begin in the pelvis, chest wall, ribs, and shoulder blades.  
4. Malignant fibrous histiocytoma
When malignant fibrous histiocytoma starts in the bones, it usually affects the long bones of the arms and legs. It tends to grow locally, though, in some cases, it may spread to distant organs such as the lungs.
It is also called pleomorphic undifferentiated sarcoma, especially when it starts in soft tissues. It is more common in middle-aged adults and very rare in children.
This form of cancer develops in the bones as well as soft tissues. Fibrosarcoma usually affects middle-aged adults. The common sites for the development of fibrosarcoma include the bones in the arms, legs, and jaw. 
6. Giant cell tumor of bone
This bone tumor can occur in benign and malignant forms. The benign form of this condition is more common. Giant cell bone cancer usually affects the arms and the legs near the knees. The risk of the spread of this cancer is comparatively less.  
Chordoma usually affects the spine and the base of the skull. It tends to affect adults over 30. It is nearly 2 times more common in men than in women.
Chordomas usually grow slowly and do not spread to other organs of the body. The tumor may recur in the same area if not removed completely during surgery. 
Other cancers that develop in bones
Other types of cancers that can affect the bones, but do not begin in the bone tissues include:
- Non-Hodgkin lymphomas
- Multiple myelomas
Cancerous changes affecting the bone marrow may lead to abnormal production of red cells, white cells, and platelets. These cells are immature and do not function efficiently. These forms of cancers are called leukemia or blood cancers.
Bone cancers can cause a wide range of symptoms depending on the type of cancer and the extent of bone involvement. Early diagnosis and appropriate treatment of bone cancers can improve the prognosis and help patients avoid relapse.