Osteosarcoma

Osteosarcoma is a type of bone cancer. In the beginning, the cancer cells appear to be regular bone cells. Then, they create malignant (cancerous) tumors, and those tumors create irregular, diseased bone.

Healthcare providers sometimes call it osteogenic sarcoma. A “sarcoma” is a type of cancer that develops in connective tissue such as bone, cartilage or muscle. “Osteo-” refers to bones. “Osteogenic” means it makes bone cells.

Osteosarcoma most commonly affects kids and teens. Experts estimate that fewer than 1,000 people in the U.S. develop osteosarcoma each year.

Which bones does osteosarcoma affect?

Osteosarcoma most often affects long bones, like the ones in your arms and legs. It usually develops near the ends of your bones around joints, especially near knees, hips or shoulders.

The bones most often affected include the:

• Shin bone (tibia)
• Thigh bone (femur)
• Upper arm bone (humerus)

Other less common locations for osteosarcoma include the:

• Jaw
• Pelvis
• Skull
• Soft tissues or organs in your abdomen (belly) and chest

Osteogenic sarcoma grades

Providers categorize osteogenic sarcomas by three grades depending on how quickly they’ll spread (metastasize):

• Low grade
• Intermediate grade
• High grade

Low-grade tumors grow slowly and usually remain where they form. A high-grade tumor will grow quickly, and is more likely to spread.