Dermoscopy of Seborrheic Keratosis: Mimickers of Melanoma

Overview / Definition Seborrheic keratosis is a common benign skin tumor characterized by its waxy, scaly appearance. These lesions are often mistaken for melanoma due to their pigmentation and irregular borders. Dermoscopy enhances the visualization of these lesions, aiding in correct diagnosis. Epidemiology Seborrheic keratosis is prevalent among adults, particularly those over the age of 40. The incidence increases with age, and both men and women are equally affected. Although they can appear anywhere on the body, they are most commonly found on the trunk, face, and scalp. Common in patients aged 40 and above. Equal gender distribution. Lesions are often multiple. Pathophysiology / Mechanism The exact etiology of seborrheic keratosis remains unclear, but it is believed to arise from the proliferation of keratinocytes in the epidermis. Genetic factors may play a role, as certain familial tendencies have been observed. UV radiation exposure may also contribute to the development of these lesions. Clinical Presentation Seborrheic keratosis typically presents as: A raised, wart-like lesion with a waxy surface. Color varies from light tan to black. Often has a stuck-on appearance. May be pruritic but is generally asymptomatic. Diagnosis / Workup The diagnosis of seborrheic keratosis is primarily clinical, supported by dermoscopic findings. Key dermoscopic features include: Presence of comedo-like openings. Keratin plugs within the lesion. Irregular, fissured surface. Fine, arborizing vessels. In uncertain cases, a biopsy may be performed to confirm the diagnosis, especially when melanoma is suspected. Treatment / Management Treatment is not required for seborrheic keratosis unless there are cosmetic concerns or discomfort. Options include: Cryotherapy: Freezing the lesion with liquid nitrogen. Curettage: Scraping the lesion off the skin. Laser therapy: Using laser technology to remove the lesion. Prognosis / Complications Seborrheic keratosis is a benign condition wi