Nonmelanoma Skin Cancer

Types

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Nonmelanoma skin cancer is classified in two stages:

• Local — Cancer cells are found only in the skin.
• Metastatic — Malignant cells have spread to nearby lymph nodes or distant organs elsewhere in the body.

Nonmelanoma skin cancer has two common types:

Basal cell carcinoma

The American Cancer Society reports that 75 percent of all skin cancer cases are diagnosed as basal cell carcinoma. This cancer develops in the lower layer of the epidermis, called the basal cell layer. Basal cell carcinoma can appear as a flat or raised, pearly, pink or red area that grows anywhere on the body. Basal cell carcinoma is most commonly found on areas of the body that receive significant exposure to the sun, such as the head and neck. The condition grows slowly, but, left untreated, it can invade surrounding tissue or even spread to other organs.

Squamous cell carcinoma

Twenty percent of skin cancers are diagnosed as squamous cell carcinoma. This condition develops in the epidermis when squamous cells divide abnormally. Squamous cell carcinoma appears as a pink, red or fleshy growth, often with whitish scales on the skin. Areas that receive high levels of exposure to the sun, such as the head, neck and top of the hands, are where squamous cell carcinoma usually develops. Squamous cell is more likely than basal cell carcinoma to spread to lymph nodes and internal organs, though this occurs in only 2 to 3 percent of patients.

Other less common types of nonmelanoma skin cancer include:

• Cutaneous lymphoma appears as pink, red or purple skin patches that slowly thicken and do not go away.
• Kaposi sarcoma develops as a patch of skin that looks bruised.
• Merkel cell carcinoma appears as red-purple nodules, usually on the face, legs or arms.
• Skin adnexal tumors appear as bumps underneath the skin.
• Skin sarcomas appear as slow-growing firm nodules under the skin's surface.