Vulvar seborrheic keratosis

Seborrheic keratoses are benign epidermal growths that are found on hair-bearing skin. Familial forms, possibly autosomal dominantly transmitted, are described, and eruptive forms of seborrheic keratosis constitute the paraneoplastic syndrome of Leser–Trelat, associated with internal malignancies. Vulvar seborrheic keratoses are exclusive to hair-bearing surfaces, are not found on mucosal surfaces, and are usually solitary. There exists controversy as to whether seborrheic keratoses are related to human papilloma virus. The histology of seborrheic keratoses in general is characterized by variable degrees of epidermal acanthosis, which usually is exophytic and characterized by a “flat bottom.” Dermoscopy may be helpful in the evaluation of seborrheic keratosis. Giant genital seborrheic keratoses have been reported, but were challenged as representing condylomata accuminata, and some feel that all seborrheic keratosis are condylomata. The most common consideration as a differential diagnosis from a histological perspective is condyloma accuminatum. Condylomata are acanthotic and have koilocytes, but may also have horn cysts.