Desmoid Tumors

Desmoid tumors are rare benign (noncancerous) tumors that develop in connective tissue — the network of tissue that supports and connects your bones, ligaments and muscles and keeps your organs in place.

You can have a desmoid tumor anywhere in your body, but they typically affect your arms, legs or belly (abdomen). Other names for desmoid tumors are deep fibromatosis, aggressive fibromatosis or desmoid fibromatosis.

Unlike cancerous tumors, desmoid tumors don’t spread. Most desmoid tumors grow slowly and don’t cause issues. But some are fast-growing and may get big enough to press on tissue, nerves or nearby organs. Healthcare providers can treat desmoid tumors, but they often come back (recur).

Types of desmoid tumors

Healthcare providers categorize desmoid tumors by location. Types include:

• Abdominal wall desmoid tumors, which affect the wall of tissue that surrounds organs in your belly, like your stomach in your upper abdomen.
• Intra-abdominal desmoid tumors, which grow in mesentery, the tissue that surrounds your intestines.
• Extra-abdominal desmoid tumors, which develop in areas other than your belly and abdominal wall. Extra-abdominal desmoid tumors typically develop in your shoulders, upper arms, chest wall and upper legs, but they can also affect your head and neck.