The first symptom of bone cancer usually begins with the onset of a fairly constant pain and/or tenderness near the cancer area. This pain is caused by the cancer stretching the periosteum (a thick membrane that covers the bone) or by stimulation of the nerves within the bone. If the pain lasts for more than a week or two and doesn't subside it should be evaluated by a physician.
Bone cancer can be diagnosed by the use of radiological tests (X-ray, bone scan, skeletal survey), surgical biopsy, blood tests or a combination of these tests. Occasionally, other radiological procedures may be used to assess bone cancer, such as computed tomography (CT) scan, magnetic resonance imaging (MRI) scan or PET scan.
Diagnosing Bone Cancer
Radiological tests (X-ray, bone scan, skeletal survey)
An X-ray is an internal picture of the bone. The cancerous area will show up as a dark spot(s) on the X-ray that appear to look like holes in the bones. A bone scan is a type of X-ray that uses radioactive particles injected into a vein. These particles circulate through the body and are selectively picked up by the bones. A high concentration of these radioactive particles appearing on the bone indicates the presence of rapidly growing cancer cells. Skeletal survey is another form of X-ray that surveys the entire skeletal system looking for blastic lesions, or lesions where extra bone has built up.
There are two types of surgical biopsy – a needle biopsy or an incisional biopsy.
- Needle biopsy - a surgeon makes a small hole in the bone and removes with a large needle a sample of tissue from the tumor
- Incisional biopsy - a surgeon slices into the tumor and removes a sample of tissue
The extracted tissue is examined under a microscope to determine if it is cancerous.
Blood tests that can detect the presence of bone cancers before they manifest as physical symptoms.
Bone cancers cause bone remodeling activity to increase. Healthy bones are constantly being broken down and rebuilt. When a bone becomes cancerous the diseased cells disrupt the balance between the osteoclasts (cells that break down bone) and the osteoblasts (cells that build bone). When these cancer cells are present in the bones, some proteins, genes, or byproducts from the osteoblasts are produced at a higher rate than during normal. Higher levels can indicate that a cancer has progressed.