Seborrheic keratosis is a benign growth of immature keratinocytes.

Epidemiology

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Seborrheic keratosis is the most common benign skin tumor in adults > 30 years of age.

Etiology

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• Associated with activating mutations of the fibroblast growth factor receptor 3.
• SK itself is benign, but rapid onset of numerous SKs (Leser-Trélat sign) is often associated with an internal malignancy (eg, gastric adenocarcinoma), possibly due to overproduction of insulin-like growth factor 1 and other cytokines.

Pathophysiology

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Clinical features

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• Single or multiple soft papules or plaques that appear stuck on
• Located on the trunk, upper extremities, face, and/or scalp
• Texture is greasy, waxy, velvety, or warty

Diagnostics

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Treatment

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