Pilomatrixoma (also known as pilomatricoma) is a slow-growing, hard mass found beneath the skin. It is most common on the face and neck, but is sometimes found elsewhere on the body. Pilomatrixoma is usually a single lump, but, occasionally, multiple masses are seen. Most cases of pilomatrixoma are diagnosed in children, but the frequency in adults is now thought to be more common.
Pilomatrixomas develop from an abnormal formation of cells that are similar to hair cells, which become hardened or calcified. The calcified cells form a mass beneath the skin.
Other members of a child's family may also have pilomatrixoma, suggesting a genetic component.
The following are the most common symptoms of pilomatrixoma. Symptoms may include:
A small, hard mass beneath the skin of the face, head, neck, or arms
The mass is usually less than 3 centimeters in diameter
The skin covering the mass appears normal, or it may feel firm or hardened
Usually, the mass is painless, unless it becomes infected
The symptoms of pilomatrixoma may look like other neck masses or medical problems. Always consult your child's health care provider for a diagnosis.
Generally, pilomatrixoma is diagnosed by physical exam. Other tests may include a biopsy--a procedure in which tissue samples are removed (with a needle or during surgery) from the body for examination under a microscope to determine if cancer or other abnormal cells are present.
Treatment may include surgery to remove the mass and some of the surrounding tissue.