What is Seborrheic Keratosis?

Seborrheic keratoses are wart-like skin lesions that occur as a normal part of the aging process of the skin. Despite their appearance, they are harmless. Yet, their appearance may mimic that of other, troublesome skin conditions, such as skin cancers. In some cases, keratoses may indicate the underlying presence of a malignancy such as gastric adenocarcinoma. They should be examined by a medical doctor when first discovered. They can appear anywhere on the body, with the exception of mucous membranes, the palms, and soles.

The Many Faces of Seborrheic Keratoses

Seborrheic keratoses have widely varying clinical features. They may be flat, or consist of a raised plaque or papule. The size range of these lesions can vary from less than 1 mm to several centimeters in diameter. A very wide palette of colors are possible, from skin-toned to yellow, light brown, dark brown, grey, black, or a mixture of several colors. The surface texture may be warty, smooth, or waxy. A single keratosis may appear, or several hundred may be grouped locally or over the entire surface of the body. Some of the most common areas for keratoses to form include the scalp, groin, under-breast, and spinal region. Generally, they appear to stick onto the surface of the skin like barnacles.

Barnacles, Brown Warts, Senile Warts, and Basal Cell Papillomas

Many alternate names exist for seborrheic keratosis, including barnacles, basal cell papillomas, brown warts, and senile warts. Almost all adults over the age of 60 have at least one of these lesions, and they tend to begin appearing on the body by the third or fourth decade of life. All races experience these spots.

What Causes Seborrheic Keratosis?

The exact cause of seborrheic keratosis remains unknown. The presence of these lesions is considered a degenerative skin condition, and they become more numerous with the passage of time. In some cases, seborrheic keratoses appear following dermatitis or sunburn. Skin friction within body folds, certain genetic mutations, and solar lentigo are associated with increased incidence rates; however, the human papilloma virus does not appear to be associated with this condition.

The term, “seborrheic keratosis,” is not a very apt description, as the condition is not seborrheic (scalp, chest, face, and upper back) in distribution, does not involve the sebaceous glands, nor does it have anything to do with sebum production.

Seborrheic Keratosis Removal and Treatment Options

Several treatments are available for removal of seborrheic keratosis lesions, with varying degrees of effectiveness and cosmetic effects. Thinner lesions lay be eradicated effectively with applications of liquid nitrogen. Curettage and electrocautery, as well as ablative laser surgery, can rapidly eliminate a lesion. Trichloroacetic acid chemical peels, shave biopsies, and other options are also available. Darker skinned patients should be aware that pigmentation loss is likely to occur following lesion removal. In most cases, lesions must be removed one-by-one.

Contact Allegheny Advanced Dermatology Center to schedule an appointment. Call: (814) 944-7109.