Non-Cancerous and Pre-Cancerous Skin Lesions

Pictures of Non-Cancerous and Pre-Cancerous Skin Lesions - Introduction

Doctor examining woman with melanoma
Peter Dazeley/Photographer's Choice/Getty Images

Not all skin blemishes are cancerous, nor will they all become cancerous in the future. This gallery of photographs will help you distinguish among cancerous, non-cancerous, and pre-cancerous lesions. Of course, diagnosing skin cancer is far from straightforward, so if you have any doubts, contact your dermatologist or primary care physician as soon as possible.

Pictures of Actinic Keratosis - On Arms

Actinic Keratosis - On Arms
Photo © A.D.A.M.

Actinic keratosis

(also called solar keratosis) is a precancerous skin lesion usually caused by too much

sun exposure

. (It may also be caused by many other factors, such as radiation or arsenic exposure.) If left untreated, actinic keratoses can develop into a more invasive and potentially disfiguring

skin cancer


squamous cell carcinoma

. They appear predominantly on sun-exposed skin, such as the face, neck, back of the hands and forearms, upper chest, and upper back. Men may develop keratoses along the rim of the ear.

Pictures of Actinic Keratosis - On Arm

Actinic Keratosis - On Arm
Photo © A.D.A.M.

For people with actinic keratosis, cumulative skin damage is caused by repeated exposure to all ultraviolet light, including that found in sunshine. Over the years, the genetic material of cells may become irreparably damaged and produce these pre-cancerous lesions. The lesions, like those seen here on the arm, may later become the more invasive cancer, squamous cell carcinoma.

Pictures of Actinic Keratosis - On Scalp

Actinic Keratosis - On Scalp
Photo © A.D.A.M.

Areas with high sun exposure such as the scalp (on bald individuals), forearms, face, and back of the neck are common sites for actinic keratoses.

Pictures of Actinic Keratosis - On Ear

Actinic Keratosis - On Ear
Photo © A.D.A.M.

These pre-malignant lesions (brown) are actinic keratoses. They are scaly and rough, and there is evidence of bleeding. They are shown here on a typical, sun-exposed area of skin.

Pictures of Actinic Keratosis - Close-Up

Actinic Keratosis - Close-Up
Photo © A.D.A.M.

Actinic keratoses

are rough and dry, which often makes them easier to feel than to see. They are initially flat and scaly on the surface, becoming slightly raised. Over time, they become hard and wart-like or gritty, rough, and "sandpapery," and may develop a horn-like texture from overgrowth of skin keratin layer (hyperkeratosis).

Pictures of Spitz Nevus

Benign juvenile melanoma, or spitz nevus
Photo © A.D.A.M.

Children may develop a benign lesion called a Spitz nevus. The mole is typically firm, raised, and pink or reddish-brown. It may be smooth or scaly and usually appears on the face, particularly the cheeks. It is not harmful, but it may be difficult to differentiate from a melanoma, even for experts.

Pictures of Atypical Nevi

congenital nevus
Photo © A.D.A.M.

Although most moles are benign, there are certain types that carry a higher risk, especially for melanoma. About 30% of the population has moles called dysplastic nevi, which are larger than ordinary moles (most are 5 mm across or larger), have irregular borders, and are various shades or colors. Individuals who have dysplastic nevi plus a family history of melanoma (a syndrome known as FAMM) are at a high risk for developing melanoma at an early age (younger than 40). Similarly, giant congenital nevi (shown in the photo), are major risk factors for melanoma. In such cases, cancer usually appears by age 10.

Pictures of Psoriasis

Photo © A.D.A.M.

Psoriasis is a skin condition that increases the risk for squamous cell carcinoma, but studies conflict on whether it has any effect on melanoma. There is some evidence that long-term treatment for psoriasis using UVA radiation (PUVA) may increase the risk for melanoma.

Pictures of Keratoacanthoma

Photo © A.D.A.M.

Keratoacanthomas are a low-grade subtype of squamous cell carcinoma. The majority occur in sun-exposed skin, usually on the hands or face. They are typically skin colored or slightly red when they first develop, but they can grow rapidly to 1 to 2 cm in size. Most will spontaneously get better within 1 year, but they almost always scar after healing. Removal by surgery (or sometimes by radiation) is recommended. In cases not appropriate for excision (due to their size or location), keratoacanthomas may be treated with 5-fluorouracil, either as a cream or by injection.

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