What is an 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.
Adamantinoma symptoms and warning signs
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
What causes an adamantinoma?
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.
Finding and diagnosing an adamantinoma
To make an adamantinoma diagnosis, your care team will ask about your symptoms and perform a physical exam. Imaging tests can help determine if you have a bone tumor and, if so, which kind.
On imaging scans, adamantinomas can look like other conditions that affect the tibia, including fibrous dysplasia, osteofibrous dysplasia, and osteomyelitis. Because of these similarities, it’s important to get any potential growth thoroughly evaluated by a team with bone sarcoma experience. Your provider may also take a sample of the tumor during an image-guided needle biopsy for closer examination.
Your options for adamantinoma care
Adamantinomas are often highly treatable. Your outlook depends on several factors, including your age, overall health, and whether the cancer has spread.
Surgery is the main treatment for adamantinoma. 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. In many cases, surgery alone can cure the tumor. Chemotherapy and radiation therapy usually aren’t needed unless the cancer has spread.
Even after successful treatment, adamantinomas can sometimes return in 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.
Why specialized adamantinoma care matters
The best treatment results come from teams that see more of these rare cancers. As home to the most comprehensive sarcoma program in the region, Penn Medicine routinely cares for complex bone tumors that other centers might only see once or twice a year.
Our dedicated sarcoma team brings together surgeons, oncologists, radiologists, and pathologists who collaborate on your care. During weekly tumor board conferences, the team reviews cases together to develop customized treatment plans and consider the latest therapies and clinical trials when appropriate.
Rated “exceptional” by The National Cancer Institute
Penn Medicine’s Abramson Cancer Center is a world leader in cancer research, patient care, and education. Our status as a national leader in cancer care is reflected in our continuous designation as a Comprehensive Cancer Center by the National Cancer Institute (NCI) since 1973, one of 7 such centers in the United States. The ACC is also a member of the National Comprehensive Cancer Network, one of a select few cancer centers in the U.S., that are working to promote equitable access to high-quality, advanced cancer care.