Primary bone cancer, a rare form of cancer, starts inside or on the surface of bone. If cancerous cells get into the bloodstream and the lymph system, they can spread to other parts of the body and affect healthy organs. Secondary bone cancer, or metastatic, is more common than primary, but still rare. Common sites of secondary bone cancer include the ribs, skull, pelvis, and vertebrae. Multiple myeloma begins in the plasma cells of bone marrow.
Plasma cells are white blood cells that produce antibodies to fight infections.
The affected bones are very fragile and many facture, even without an injury. Such a fracture may be the first sign that a person has bone cancer. Bone cancer of the spine may collapse or crush vertebrae. As a result, the spinal cord could be damaged, causing weakness or even paralysis of the affected limbs. Your doctor will examine the affected area and ask about the history of the pain and swelling in your bones or joints.