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Seborrheic Keratoses

 
        •  What Are They?
 
        •  Symptoms
 
        •  Diagnosis
 
        •  Expected Duration
 
        •  Prevention
 
        •  Treatment
 
        •  When To Call A Professional
 
        •  Prognosis
 
        •  Additional Info
 

What Are They?

Seborrheic keratoses are benign (noncancerous) skin growths that develop from skin cells called keratinocytes. These growths have a waxy or greasy look and can be tan, brown or black. They look like they have been glued or stuck onto the skin. Over time, the growths become rough and crusty looking.

Seborrheic keratoses usually appear alone, but others may develop. They usually are found on the chest and back but can appear anywhere on the body, including the face, scalp and neck.

No one knows what causes seborrheic keratoses, but they become more common with age. Most people will develop some seborrheic keratoses as they get older, and children rarely have them. Seborrheic keratoses are not contagious.

Symptoms

Seborrheic keratoses look like crusty growths on the skin that typically start out tan or brown but can darken over time. They tend to have a greasy appearance and look as though they were glued onto the skin, as opposed to growing from it. They may be tiny, or larger than 3 inches across. They rarely itch.

Diagnosis

Physicians usually can diagnose seborrheic keratoses by looking at them. In rare cases, seborrheic keratoses may look like other skin disorders, including malignant melanoma. If the diagnosis is uncertain, your physician may want to do a biopsy, in which a portion of the growth is removed and examined under a microscope.

Expected Duration

Seborrheic keratoses do not go away on their own. If they are not removed, they will last a lifetime.

Prevention

There is no way to prevent seborrheic keratoses from developing.

Treatment

Seborrheic keratoses do not require treatment. Although they may grow relatively large and can become dark, they are not dangerous.

If seborrheic keratoses become irritated, itchy or unsightly or if they bleed, they can be removed in a doctor's office. Because the skin is numbed before any procedure, treatment is mostly painless. The three main methods of removal are:

  • Curettage After the skin is numbed, the growths are sliced or scraped off using an instrument called a curette.
  • Cryosurgery or freezing Liquid nitrogen is applied to the growths. The seborrheic keratoses crust over and then fall off a few weeks later.
  • Electrosurgery An electric current burns the growths off.

When To Call A Professional

See a health care professional if you develop any unusual skin growths or if existing growths start to change their appearance. If multiple seborrheic keratoses develop suddenly, call your physician's office to schedule an appointment. It may be a sign of another disease.

Prognosis

Seborrheic keratoses do not go away on their own, but they can be removed if they become irritating or unsightly. There is no harm in not treating the growths, because they are benign (noncancerous) and do not become cancerous.

Additional Info

American Academy of Dermatology

P.O. Box 4014

Schaumburg, IL 60168-4014

Phone: (847) 330-0230

Toll-Free: (888) 462-3376

Fax: (847) 330-0050

http://www.aad.org/

 
 
Publication Source: Harrison's Principles of Internal Medicine, 14th edition. A.S. Fauci, E. Braunwald, K.J. Isselbacher, et al, (eds). New York, NY: McGraw-Hill Companies, 1998
Publication Source: Harvard Medical School Family Health Guide
Publication Source: Mosby's Medical, Nursing, & Allied Health Dictionary, 4th edition. K.N. Anderson, ed. St. Louis, MO: Mosby?Year Book, Inc., 1994
Publication Source: Stedman's Medical Dictionary, 27th edition. Lippincott Williams & Wilkins, 2000
Online Source: American Academy of Dermatology http://www.aad.org/default.htm
Online Medical Reviewer: LeWine, Howard MD
Date Last Reviewed: 3/18/2005
Date Last Modified: 4/20/2005

Source: from Harvard Health Decision Guides, Harvard Health Publications, Copyright © 2007 by President and Fellows of Harvard College. All rights reserved. Used with permission of StayWell.
 
Symptom Checker content copyright © 2006 by President and Fellows of Harvard College. All rights reserved. Used with permission of StayWell. Use of content is subject to Terms & Conditions and Medical Disclaimer. More information on Harvard Medical School's publications and services is available at http://www.health.harvard.edu.

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