Epidermoid cysts (eh-peh-DER-moyd sists) are small bumps that develop beneath the skin on your face, neck, trunk and sometimes your genital area. Slow-growing and often painless, they rarely cause problems or need treatment.

Although many people refer to epidermoid cysts as sebaceous cysts, they’re different. True sebaceous cysts are less common, and they arise from the glands that secrete oily matter that lubricates hair and skin (sebaceous glands). Epidermoid glands arise from the cells that make up the outer layers of skin (epidermal).

If the appearance of an epidermoid cyst bothers you, or if the cyst ruptures or becomes infected, it can be surgically removed. Epidermoid cysts are almost always noncancerous, but in rare cases, they can lead to skin cancers.

Jun. 07, 2011