What is Bone Cancer?
As the name suggests, bone cancer refers to the abnormal cell mass, a tumor that forms in a bone tissue. The tumor may arise in the bone or may have spread to the bone, originating in another area. The most commonly diagnosed bone cancers are malignant tumors in which the cell mass is dividing excessively, resulting in the growth of a tumor and its spreading to the other parts. Cancers originating in the bone, also called primary bone cancer, however, are rare and constitute less than 1% of the diagnosed cases for bone cancer. The focus of this blog post is the primary bone cancer that is a bone cancer in the true sense.
Types of Bone Cancer
There are different types of primary bone cancer that differ in the region of the bone tissue that is affected. These include:
Multiple Myeloma (MM) is the most common type of primary bone cancer. As the name indicates, there are various patches on the bone where it grows. Unlike other types of bone cancers that originate in the bone itself, the cancer cells proliferate unchecked in the bone marrow resulting in a number of blood cells and bone problems such as the formation of osteolytic lesions, bone thinning and bone pain. Usually, older adults are affected by Multiple Myeloma.
Osteosarcoma (Osteogenic Sarcoma) is cancer that occurs in the bone itself, affecting the outer layer of the hard tissue that provides a protective covering to the bone. Osteosarcoma is likely to originate in the long bones of arms and legs, arising at their tips but may also develop in other locations including pelvic and shoulder bones. Mostly diagnosed in children and adolescents but can also develop in adults.
Chondrosarcoma begins in the cartilage tissue that is a tough connective tissue between the bones. The region most affected by Chondrosarcoma are the pelvis, shoulders, and thighs. It generally affects older adults.
A very rare form of bone cancer that begins forming in the soft tissues that surround the bones. The bones commonly affected by Ewing’s sarcoma are the long bones of the arms and legs, backbone and pelvic bones. It is typically found in children and young adults.
Symptoms of Bone Cancer
Like other types of cancer, the symptoms vary for different types of bone cancer and from patient to patient. Moreover, the severity of symptoms varies with the size of the tumor and its location. The symptoms reported by most patients and are a potential warning signal are:
- Lumps or swelling in the affected bones
- Severe bone pain
- Deep bone pain even at rest
- Weak bones and bone fractures
- Weight loss
Where the symptoms are a possible indication, they are not enough to be certain about the cause of these symptoms, as they overlap with other diseases and infections. Only detailed examination and diagnostic tests such as MRI, X-rays, and biopsy can confirm the diagnosis.
Causes of Bone Cancer
The causes of bone cancer are not well known. A number of factors contribute to the abruption of normal cell cycle and the development of cancer and it is not possible to identify the factor that triggered the abnormal division of cells. The factors known to play a significant role in causing cancer are exposure to radiation and genetics. People who receive radiation therapy to kill other cancerous cells sometimes develop Osteosarcoma. Also, some diseases and syndrome are a potential risk factor for developing bone cancer, for instance, Paget’s disease, a condition in which bones break and grow again, mostly abnormally.