Symptoms

Epidermoid cyst signs and symptoms include:

• A small, round bump under the skin, usually on the face, neck or trunk
• A tiny blackhead plugging the central opening of the cyst
• A thick, yellow, smelly material that sometimes drains from the cyst
• Redness, swelling and tenderness in the area, if inflamed or infected

When to see a doctor

Most epidermoid cysts don't cause problems or need treatment. See your doctor if you have one or more that:

• Grows rapidly
• Ruptures or becomes painful or infected
• Occurs in a spot that's constantly irritated
• Bothers you for cosmetic reasons
• Is in an unusual location, such as a finger and toe