They are more common in light-skinned individuals. Also known as a senile verruca and seborrheic wart, this is a benign epithelial neoplasm that can occur on any part of the body. The reticulated type is usually found on the sun-exposed areas of the face and eyelids, and may develop from solar lentigines. These lesions usually affect middle-aged and older adults.
CLINICAL PRESENTATION Seborrheic keratoses initially present as painless, movable, sharply defined slightly elevated macules with a variable degree of pigmentation that varies from tan to brown. They sometimes appear in large numbers. As they grow they typically develop a greasy papil-lomatous or verrucous, stuck-on appearance. They are usually sessile, but can sometimes be pedunculated. Older lesions tend to be more verrucous and folded, with multiple keratin plugs creating a pitted surface. Irritation can cause inflammation, swelling, and sometimes bleeding, and crusting. In the variant called dermatosis papulosa nigra a large number of darkly pigmented lesions occurs on the cheeks of black patients. A rapid increase in size and number may represent the sign of Leser-Trelat (multiple eruptive seborrheic keratosis), which may occur in patients with an occult malignancy.
HISTOPATHOLOGY Seborrheic keratoses are sharply defined tumors that have multiple histological types that overlap frequently [acanthotic, papillomatous (hyperkeratotic), adenoid [reticulated], irritated, and clonal]. Acanthotic seborrheic keratoses (shown below) are encountered most frequently and are composed of broad columns of basaloid cells that interdigitate. Varying amounts of
squamoid cells are admixed with the basaloid cells. Invaginations of keratin and horn cysts are typical features of acanthotic seborrheic keratosis.
TREATMENT These lesions are primarily of cosmetic concern only, although they can be an annoyance when they rub or catch on clothing. They may be removed for biopsy or cosmesis, or to prevent irritation. Therapy includes light cryotherapy followed by curettage, laser ablation, and surgical excision. They usually do not recur after treatment. Malignant melanoma has been reported within a seborrheic keratosis. In up to 10% of lesions they may not be able to be distinguished from melanoma so that biopsy is appropriate if there is any doubt about the diagnosis.
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Complete Guide to Preventing Skin Cancer. We all know enough to fear the name, just as we do the words tumor and malignant. But apart from that, most of us know very little at all about cancer, especially skin cancer in itself. If I were to ask you to tell me about skin cancer right now, what would you say? Apart from the fact that its a cancer on the skin, that is.