Adamantinoma

An adamantinoma is a particularly rare, malignant (cancerous) tumor that starts in bones. Among primary bone cancers—also known as bone sarcomas—adamantinomas represent just 1 percent of cases.

Adamantinomas appear most often in men, after their bones have fully developed. The tumors most often form as lumps in the shin bone (tibia). They can also affect the fibula bones (the second bone in the lower leg). Less often, adamantinomas occur in other bones.

Adamantinomas are slow-growing tumors, but they can damage surrounding bone. If they grow large enough, they may eventually invade nearby soft tissues, including muscles. In 15 percent to 20 percent of cases, these tumors metastasize (spread) to other parts of the body, mainly affecting the lungs and less commonly the lymph nodes and other bones.

The Sarcoma Program at Penn Medicine’s Abramson Cancer Center provides one of the nation’s most experienced adamantinoma care teams.

Most cancerous bone tumors, including adamantinoma, cause pain. Depending on the location and size of the tumor, you may experience symptoms such as:

• Bone pain from tumor damage
• Difficulty moving the leg, possibly causing a limp
• Noticeable lump on the shin bone
• Odd-looking lower leg with a bowed or curved shin bone
• Swelling and pain near the tumor

Researchers do not yet know what causes an adamantinoma. Currently, there isn’t anything you can do to reduce your risk of developing one of these rare tumors.

Studying these tumors is challenging because they are so rare. Unlike some other bone cancers, no evidence exists that adamantinomas run in families or have ties to previous medical treatments.

Adamantinomas are often highly treatable. Individual outlook depends on a number of factors, including age, overall health, and whether the cancer has spread. The best treatment results come from teams that see more of these rare cancers.

Adamantinomas are treated with surgical removal. Our team is skilled in the most effective approach, which removes the entire tumor in one piece with a bit of normal tissue on all sides. Complete removal is often enough to cure an adamantinoma. Chemotherapy or radiation therapy typically aren’t used unless the cancer has spread.

Even with appropriate treatment, adamantinomas sometimes recur (return) in the same area of the tibia. To protect your health, we follow you closely after treatment. Regular checkups ensure that if cancer does return, we can treat it quickly.