What is a Sebaceous Adenoma?

A sebaceous adenoma is a small, slow-growing tumor that typically forms in the sebaceous, or oil-producing, glands of the skin. Sebaceous adenoma is considered to be a benign skin tumor, although it can grow back after surgical removal. These tumors mostly grow on the scalp, face and neck, but have been known to appear on other parts of the body. Both men and women can develop these tumors, which generally appear after 50 years of age. While often not serious, they can sometimes indicate Muir-Torre syndrome, a serious genetic illness.

This tumor of the sebaceous glands usually appears as a tiny nodule on the surface of the skin. Most sebaceous adenomas are smaller than 1 cm (0.39 inches) in diameter. Tumors larger than 5 cm (1.96 inches) have been reported.

Sebaceous adenomas are usually smooth and yellowish in color. The surface may be mottled. Sometimes these tumors can take on physical characteristics similar to those of cancerous skin tumors. Physicians often recommend the removal and biopsy of tumors with unusual characteristics.

While sebaceous adenomas often aren't serious, they can sometimes be a symptom of Muir-Torre syndrome (MTS). This inherited disorder typically causes multiple sebaceous adenomas, combined with skin cancer and other cancers. MTS is considered a fairly rare disease. It can affect people of all ages, though most people who have it begin to show symptoms in their early 50s.

MTS is considered to be a genetic predisposition to sebaceous adenoma and multiple forms of cancer, including sebaceous carcinoma, a cancerous tumor of the sebaceous glands. Many patients develop colon cancer, reproductive cancers, or cancers of the urinary tract. Large cancerous tumors of the eyelids are considered common in MTS patients. MTS is usually fatal in about half of patients who develop it. Patients who have multiple sebaceous adenomas may be advised to undergo an MRI, CT scan, or other imaging process.

For patients who do not have Muir-Torre syndrome, there may be little need to surgically remove the sebaceous adenoma. These tumors are believed incapable of spreading or growing fast enough to cause harm to physical structures. Tumors that do not show unusual characteristics, and are not indicative of MTS, may be left alone.

A sebaceous adenoma may be removed if it is troublesome to the patient, or for cosmetic reasons. Though considered benign, these tumors can often grow back if they are not completely removed.