Adenomas

What are adenomas?

Adenomas are benign (noncancerous) tumors. They start in the tissues that line your organs and glands, called epithelial tissue. They are a type of polyp and are also referred to as adenomatous polyps.

Adenomas usually grow slowly. If they are small, doctors often monitor them without the need for treatment. If they are large, surgery may be recommended.

Adenomas can sometimes turn into cancer. It is important that your doctor monitors the adenoma and treats them if needed.

Are there different types of adenomas?

The most common types of adenoma are those that grow on our glandular organs. These are the organs which make and release hormones to regulate many bodily functions.

Adenomas are referred to as functioning, meaning they secrete excess hormones, or nonfunctioning, which don’t produce any hormones and often cause no noticeable symptoms.

Other types of adenomas include:

• Adrenal adenomas: These adenomas form on the adrenal glands.
• Colon adenomas: A type of polyp, these adenomas grow on the lining of the colon. Larger polyps are called advanced adenomas.
• Parathyroid adenomas: These appear on the parathyroid glands and cause overproduction of the parathyroid hormone.
• Pituitary adenomas: These include both microadenomas and macroadenomas.
• Pleomorphic adenomas: These form in the salivary glands.
• Sebaceous adenomas: These form in oil-producing glands.

Adenomas are characterized according to how they grow:

• Tubular: Small adenomas which are round or oval in shape.
• Villous: Have a cauliflower-like appearance, usually common in larger adenomas.
• Tubulovillous: A mix of both villous and tubular growth patterns.
• Sessile: A larger base with a flattened shape.
• Serrated: Appears to have a jagged pattern.
• Sessile serrated: A mixture of serrated and sessile patterns.

What are the symptoms of an adenoma?

The symptoms of adenomas will depend on where they are located. Some smaller adenomas may cause no symptoms.

In general, the signs and symptoms of adenomas include:

• Fatigue
• Abdominal pain
• Headache
• Muscle weakness
• Iron-deficiency anemia
• Rectal bleeding
• Nausea or vomiting

Adenomas are benign tumors, however they can lead to complications if they grow and begin to press on nearby organs or interrupt hormone production. The severity of complications caused by an adenoma will vary depending on its location and size.

What causes adenomas?

If our cells grow and divide in an uncontrolled way, then an adenoma may develop. This is also how cancerous tumors develop, but adenoma grow much slower and are less aggressive.

What are the risk factors for adenomas?

• Age: Pituitary adenomas are more common is adults aged 30 – 50.
• Genetic conditions: Things like multiple endocrine neoplasia type 1, an inherited condition, increase the likelihood of adenomas developing.
• Genetic diseases: Things like familial adenomatous polyposis, can increase risk.
• Gender: Women are more likely to develop parathyroid adenomas.

How are adenomas diagnosed?

Your doctor will perform a physical exam and look closely at your medical history. They may also order imaging tests, such as a CT, MRI or PET scan.

A small sample of tissue may be taken from the adenoma, called a biopsy, for closer examination in a laboratory.

How are adenomas treated?

Treatments for adenoma include:

• Active surveillance: If the adenoma is small and not causing health problems, your doctor may ‘watch-and-wait’.
• Medication: These may be prescribed if the adenoma is causing hormone issues.
• Surgery: A larger adenoma is more likely to become cancerous, so usually, any adenoma that is over 5 millimeters will be removed. An adenoma will also be removed if it is causing health problems.

Can adenomas be prevented?

Many of the risk factors for adenomas can’t be controlled, therefore it isn’t always possible to prevent them. However, adopting a healthier lifestyle and attending cancer screening may improve your chances of staying healthy. If you are at a higher risk of developing an adenoma, discuss screening with your doctor.

If an adenoma is treated, if usually responds well. Most adenomas don’t develop into cancer.