Verrucous melanoma masquerading as a seborrheic keratosis

Abstract

Seborrheic keratosis is a benign condition that can mimic many different non-melanoma and melanoma neoplasms. There have been several case reports of underlying squamous cell carcinomas or intraepidermal carcinomas appearing within lesions that look analogous to seborrheic keratoses. We present a patient with a verrucous melanoma that could be mistaken for a benign skin tumor like an inflamed seborrheic keratosis. In our patient’s case, her verrucous plaque was initially clinically suggestive of a benign seborrheic keratosis. However, given the patient’s complaint of pain associated with the lesion, a biopsy was performed and revealed a verrucous-keratotic malignant melanoma, which was subsequently removed through surgical excision. It is important to remain vigilant of this diagnosis, as treatment for inflamed seborrheic keratosis often includes a trial of cryotherapy, which potentially could lead to a delayed diagnosis of an underlying malignant lesion.