by Robyn Ndikumana MD FRCPC
November 2, 2022
Xanthelasma (pronounced “zan-the-las-ma”) is a non-cancerous growth made up of fat-filled immune cells called histiocytes. Histiocytes are specialized cells that help remove waste products from the body. Xanthelasmas appear as small, yellow bumps on the upper, and sometimes lower, eyelids. Xanthelasma is a type of xanthoma.
Xanthelasma develops in people who have high blood cholesterol levels. These growths are especially common in people with diabetes or other genetic conditions leading to high blood cholesterol levels.
Xanthelasma usually occurs in patients who are middle-aged or older. However, if it occurs in younger patients, it may be a sign of familial hypercholesterolemia, which is a genetic condition resulting in high blood cholesterol levels.
Your doctor may suspect that a bump on your eyelid is a xanthelasma based on the look and location of the growth. The diagnosis can be confirmed after a small tissue sample is removed in a procedure called a biopsy.
The diagnosis of xanthelasma is important because it may be the first sign that a patient has high blood cholesterol levels. If you have been diagnosed with xanthelasma, please talk with your doctor to see if additional tests for blood cholesterol are appropriate for you.
When examined under the microscope a xanthelasma is made up of many lipid-filled (fat-filled) histocytes. Pathologists sometimes describe these cells as foamy histiocytes because the inside of the cell looks like it is filled with a clear foam. Because they are full of lipids, the foamy histiocytes in a xanthelasma are much larger than normal histiocytes.