Sebaceous cystEpidermal cyst; Keratin cyst; Epidermoid cyst; Epidermal inclusion cyst
A sebaceous cyst is a closed sac under the skin filled with a cheese-like or oily material.
Sebaceous cysts most often arise from swollen hair follicles. Skin trauma can alsocause a cyst to form. A sac of cells is created into which a protein called keratin is secreted.
The main symptom is usually a small, non-painful lump beneath the skin. The lump is usually found on the face, neck and trunk. It usually grows slowly and is not painful.
If the lump becomes infected or inflamed, other symptoms may include:
- Skin redness
- Tender or sore skin
- Warm skin in the affected area
- Grayish-white, cheesy, foul-smelling material that drains from the cyst
Exams and Tests
In most cases, your doctor can make a diagnosisby examining your skin. Sometimes, a biopsy may be needed to rule out other conditions.
Sebaceous cysts are not dangerous and can usually be ignored. Placing a warm moist cloth (compress) over the area may help the cyst drain and heal.
If you have a small inflamed cyst, your doctor may inject it with a steroid medicine that reduces swelling.
If the cyst becomes swollen, tender, or large, your doctor may drain it or perform surgery to remove it.
Cysts may become infected and form painful abscesses.
Cysts may return, evenafter they are surgically removed.
When to Contact a Medical Professional
Call your health care provider if you notice any new growths on your body. Although cysts are not dangerous, your doctor should examine you for signs of skin cancer.
Habif TP. Clinical Dermatology: A Color Guide to Diagnosis and Therapy. Philadelphia, Pa.: Elsevier Mosby; 2009:chap 20.
Review Date: 5/15/2013
Reviewed By: Kevin Berman, MD, PhD, Atlanta Center for Dermatologic Disease, Atlanta, GA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.