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Symptoms
By Mayo Clinic staff
A seborrheic keratosis usually has the appearance of a waxy or wart-like growth. It typically appears on the head, neck or trunk of the body. A seborrheic keratosis:
- Ranges in color, usually from light tan to brown or black
- Is round or oval shaped
- Has a characteristic "pasted on" look
- Is flat or slightly elevated with a scaly surface
- Ranges in size from very small to more than 1 inch (2.5 centimeters) across
- May itch
You may develop a single growth or cluster of growths. Though not painful, seborrheic keratoses may prove bothersome depending on their size and location. Be careful not to rub, scratch or pick them. This can lead to inflammation, bleeding and, in rare cases, infection.
When to see a doctor
See your doctor if:
- Many growths develop over a short time of a few weeks to months. Normally, seborrheic keratoses appear one or two at a time over many years.
- The growths get irritated or bleed when your clothing rubs against them. You may want the growths removed.
- You notice suspicious changes in your skin, such as sores or growths that grow rapidly, bleed and don't heal. These could be signs of skin cancer.
References
- Thomas VD, et al. Benign epithelial tumors, hamartomas, and hyperplasias. In: Wolff K, et al. Fitzpatrick's Dermatology in General Medicine. 7th ed. New York, N.Y.: McGraw-Hill Companies, Inc.; 2008. http://www.accessmedicine.com/popup.aspx?aID=2981822. Accessed Sept. 15, 2010.
- Seborrheic keratoses. The Merck Manuals: The Merck Manual for Healthcare Professionals. http://www.merck.com/mmpe/print/sec10/ch127/ch127h.html. Accessed Sept. 16, 2010.
- Seborrheic keratoses. American Academy of Dermatology. http://www.aad.org/public/publications/pamphlets/common_seb_keratoses.html. Accessed Sept. 15, 2010.
- Habif TP. Benign skin tumors. In: Habif TP. Clinical Dermatology: A Color Guide to Diagnosis and Therapy. 5th ed. Philadelphia, Pa.: Mosby Elsevier; 2009. http://www.mdconsult.com/books/page.do?eid=4-u1.0-B978-0-7234-3541-9..00029-8&isbn=978-0-7234-3541-9&sid=1054258674&type=bookPage§ionEid=4-u1.0-B978-0-7234-3541-9..00029-8--s0010&uniqId=218874618-7#4-u1.0-B978-0-7234-3541-9..00029-8--s0010. Accessed Sept. 16, 2010.
- Seborrheic keratoses. American Osteopathic School of Dermatology. http://www.aocd.org/skin/dermatologic_diseases/seborrheic_keratos.html. Accessed Sept. 15, 2010.
- Culbertson GR. 532-nm diode laser treatment of seborrheic keratoses with color enhancement. Dermatologic Surgery. 2008;34:525.
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