Desmoid Tumors – Symptoms and Causes
Overview
Desmoid tumors are rare growths that develop in the connective tissues. These tumors don’t spread to other parts of the body but can grow into surrounding tissues and organs. They affect about 2-4 people per million each year.
The exact cause remains unclear, but researchers have identified genetic and hormonal influences that may increase a person’s risk. In some cases, these tumors are linked to inherited conditions.
Signs and Symptoms
Desmoid tumors often grow slowly and may not cause symptoms at first. When they do appear, symptoms depend on the tumor’s location, size, and impact on nearby tissues or organs.
Common symptoms include:
- A lump or swelling that may or may not be painful
- Pain or discomfort in the affected area
- Limited movement in nearby joints
- Bowel blockage (if tumors are in the abdomen)
- Feeling of fullness or bloating
- Trouble breathing (if tumors press on the lungs)
Symptoms can get worse as the tumor grows and puts pressure on nearby tissues, nerves, and organs. While these tumors don’t spread to other parts of the body, they can grow into surrounding tissues.
When To Contact a Healthcare Provider
See your doctor if you notice:
- A lump that grows or doesn’t go away
- Unexplained pain that persists for more than two weeks
- Pain that wakes you up at night
- Swelling that interferes with daily activities
- Trouble with normal bodily functions depending on tumor location
Early diagnosis helps with treatment planning. Your doctor may refer you to a specialist who has experience with desmoid tumors.
What Causes Desmoid Tumors
Desmoid tumors develop when cells in the connective tissues start growing abnormally. These rare growths are not cancer, but they can be aggressive and invasive locally.
Genetic factors play a significant role in the development of desmoid tumors. People with a condition called familial adenomatous polyposis (FAP) have a higher risk of developing these tumors.
This inherited condition causes hundreds of polyps to form in the colon and rectum.
Mutations in the beta-catenin gene (CTNNB1) appear in many desmoid tumors. This gene helps control cell growth and division. When it changes, cells may grow out of control.
Hormonal influences might affect desmoid tumor growth. Some research suggests that estrogen may play a role, which might explain why these tumors:
- Are more common in women of reproductive age
- Sometimes grow during pregnancy
- May change in size with hormonal fluctuations
Physical trauma to tissues might trigger desmoid tumor formation in some cases. This includes:
- Surgery scars
- Injuries to muscles or connective tissues
- Repeated trauma to specific areas
Most desmoid tumors appear sporadically with no clear cause.
Risk Factors
Several factors may increase the chance of developing desmoid tumors:
- Genetic conditions: People with familial adenomatous polyposis (FAP) or Gardner syndrome have a significantly higher risk.
- Hormonal influences: Tumors are more common in women aged 20–40, especially during or after pregnancy.
- Tissue injury or surgery: Prior surgery, injury, or chronic physical stress may raise the chance of tumor formation.
- Other possible contributors include immune system irregularities and chronic inflammation, though more research is needed.
