Bone cancer is a malignant (cancerous) bone tumor that destroys normal bone tissue. Not all bone tumors are malignant. In fact, benign (non-cancerous) tumors of the bone are more common than malignant tumors. Both malignant and benign bone tumors can grow and compress healthy bone tissue, but benign tumors do not spread, do not destroy bone tissue, and are rarely life-threatening.
This horrible disease begins in bone tissue called primary bone cancer. Cancer that metastases (spreads) to bones in other parts of the body, such as the breasts, lungs, and prostate is called metastatic cancer and is named after the organ or tissue in which it started. Primary bone cancer is much less common than cancer that spreads to the bone.
It is common for patients with bone cancer to have pain in the affected bone. At first, the pain is not constant. It may be worse at night or when the bone is used (for example, pain in the legs when walking). As the cancer grows, the pain will be constant. Pain increases with activity and can cause lameness if the leg is affected.
The most common types of primary bone cancer include:
- Osteosarcoma, which originates in the osteoid tissue of the bone. This tumor most often occurs in the knee and humerus (arm).
- Chondrosarcoma, which originates in cartilage tissue. Cartilage cushions the ends of the bones and covers the joints. Chondrosarcoma most commonly occurs in the pelvis (located between the hip bones), the upper leg, and the shoulder. Chondrosarcoma sometimes contains cancer bone cells. In that case, doctors classify the tumor as an osteosarcoma.
- Tumors in the Ewing sarcoma family of tumors (ESFT), which generally originate in bone, but can also originate in soft tissues (muscles, adipose (fat) tissue, fibrous tissue, blood vessels, and other supporting tissues). Scientists believe that ESFTs originate from elements of immature nervous tissue in bone or soft tissue. ESFTs occur most frequently along the spine and pelvis, and in the legs and arms.
Other cancers that start in soft tissue are called soft tissue sarcomas. These do not constitute bone cancer and therefore are not described in this resource.
