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Sebaceous cyst - Overview

Alternative Names

Epidermal cyst; Keratin cyst; Epidermoid cyst

Definition of Sebaceous cyst:

A sebaceous cyst is a closed sac under the skin filled with a cheese-like or oily material.

Causes, incidence, and risk factors:

Sebaceous cysts most often arise from swollen hair follicles. Skin trauma can also induce a cyst to form. A sac of cells is created into which a protein called keratin is secreted.

These cysts are usually found on the face, neck, and trunk. They are usually slow- growing, painless, freely movable lumps beneath the skin. Occasionally, however, a cyst will become inflamed and tender.

Hair follicle anatomy

Reviewed last on: 4/12/2007
Kevin Berman, MD, PhD, Associate, Atlanta Center for Dermatologic Disease, Atlanta, GA. Review provided by VeriMed Healthcare Network.

References

Habif TP. Clinical Dermatology. 4th ed. St. Louis, Mo: Mosby; 2004.

Roberts JR, Hedges JR. Clinical Procedures in Emergency Medicine. 4th ed. Philadelphia, Pa: WB Saunders; 2004.

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