Adenoma

An adenoma is a benign (noncancerous) tumour that forms from glandular cells. Glandular cells are specialized cells that produce and release important substances, such as mucus or enzymes, to help organs function properly. Adenomas are typically harmless, but they can sometimes develop into cancer over time.

What causes an adenoma?

The exact cause of an adenoma depends on the type of adenoma and where it is located in the body. Genetics, diet, hormones, and lifestyle factors can all play a role. For example, adenomas in the colon are often influenced by dietary factors and genetics, while adenomas in the breast or thyroid gland may be more affected by hormonal influences. Chronic inflammation or ongoing irritation can also contribute to the formation of adenomas in specific organs.

Where are adenomas commonly found?

Adenomas can develop in various body parts, including the colon, stomach, thyroid gland, adrenal glands, salivary glands, kidneys, breast, bladder, uterus (endometrium), and cervix.

Common types of adenomas include:

• Pleomorphic adenoma (often in salivary glands).
• Tubular adenoma (usually found in the colon).
• Fibroadenoma (commonly seen in the breast).
• Follicular adenoma (typically occurs in the thyroid gland).

What is the difference between an adenoma and a polyp?

An adenoma is a specific type of benign tumour composed of glandular cells. A polyp, on the other hand, is a general term that describes any growth that extends from a mucosal surface, such as the lining of the colon or stomach. While some polyps are adenomas, not all polyps are adenomas—polyps can also be inflammatory or composed of other cell types.

What is the risk of an adenoma turning into cancer?

Although adenomas are benign, some have the potential to become cancerous over time. The risk depends on factors such as the type and location of the adenoma and whether your pathologist identifies changes called dysplasia (abnormal cells that can become cancer). Regular follow-up and removal of certain adenomas, especially those in the colon, can help prevent cancer from developing.

About this article

Doctors wrote this article to help you read and understand your pathology report. Contact us if you have questions about this article or your pathology report. For a complete introduction to your pathology report, read this article.