Seborrheic Keratosis Flat Lesions
Flat seborrheic keratoses are seen most often on the extremities. They may mimic spreading pigmented actinic keratosis or superficial spreading melanoma. If doubt exists, a skin biopsy should be performed. Although seborrheic keratoses have no malignant potential, there are rare reports of melanoma, basal cell carcinoma and squamous cell carcinoma developing within a seborrheic keratosis. A biopsy should be performed for a significantly changing seborrheic keratosis.