Seborrheic keratosis

Alternative names
Benign skin tumors - keratosis; Keratosis - seborrheic; Senile keratosis

Seborrheic keratosis is the presence of benign wart-like growths on the surface of the skin.

Causes, incidence, and risk factors
Seborrheic keratosis is a benign form of skin tumor. The origin is unknown. It commonly appears after age 40.

The tumors appear as wart-like growths in a variety of colors. They may appear in large numbers on the surface of the body. They are usually painless and benign, but may become irritated and itch. They may be cosmetically disfiguring and psychologically distressing as a result.


  • skin growths       o located on the face, chest, shoulders, back, or other areas       o yellow, brown, black, or other colors       o surface is slightly elevated, flat       o may have a rough or wart-like texture       o often waxy surface       o round to oval shape       o “pasted on” appearance       o may be single, but are usually multiple growths

Signs and tests
Diagnosis is based primarily on the appearance of the growths. A skin lesion biopsy may be used to confirm the diagnosis.

Treatment is usually not required unless the growths become irritated or are cosmetically displeasing.

If treatment is needed, growths may be surgically removed or removed by cryotherapy (freezing).

Expectations (prognosis)

Seborrheic keratosis is a benign and usually painless condition. Removal of the growths is simple and usually does not result in scars. However, growths on the trunk often leave lighter-colored skin. Particular growths usually do not recur after removal, but people who are prone to this condition may develop more in the future.


  • psychological distress from change in appearance  
  • irritation, discomfort of growths  
  • misdiagnosis (malignant melanoma may be difficult to differentiate in some cases)

Calling your health care provider
Call for an appointment with your health care provider if you have symptoms suggestive of seborrheic keratosis.

Also call if new symptoms develop, including change in the appearance of the skin growth or development of other lesions.

Johns Hopkins patient information

Last revised: December 3, 2012
by Levon Ter-Markosyan, D.M.D.

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