Skin cancer facts:
- Each year in the United States, more than 1 million people will be diagnosed with types of skin cancer called basal cell or squamous cell carcinomas – collectively called nonmelanoma skin cancer. These diseases are by far the most common types of cancer in humans.
- Basal cell carcinoma accounts for almost a quarter of all cancers in the United States.
- Nonmelanoma skin cancers are usually highly curable diseases, especially when detected and treated early.
- Melanoma, the most serious form of skin cancer, is diagnosed in about 59,000 people annually and was expected to cause 7,800 deaths during the past year. It is highly curable, however, with early detection and proper treatment.
Skin cancer, the most common of all cancers, is a disease in which malignant cells are found in one of the layers of the skin.
Skin consists of two main layers: the dermis (inner layer) and the epidermis (top layer). The dermis contains blood vessels, hair follicles, sweat glands and oil glands. The epidermis consists of mostly flat, scale-like cells known as squamous cells. Beneath the squamous cells are round basal cells. Melanocytes are in the epidermis. They contain melanin, the pigment of the skin. When you expose your skin to the sun (or ultraviolet light in a tanning bed), the melanocytes produce more pigment, causing your skin to darken.
Several types of cancer can start in the skin. The most common are basal cell cancer and squamous cell cancer. These types are called nonmelanoma skin cancer. They are usually highly curable, especially when detected and treated early.
Basal cell carcinoma usually occurs on areas of your skin that have been exposed to the sun. It appears as a small raised bump that has a smooth, pearly appearance or a persistent red scaly patch. Basal cell cancers may spread to surrounding tissue, but usually do not spread to other parts of the body.
Squamous cell carcinoma tumors also occur on areas of sun-exposed skin, often on the nose, ears, lips and hands. This cancer appears as a firm red bump. These tumors sometimes spread to the lymph nodes.
Malignant melanoma, a potentially more serious cancer, begins in the skin pigment cells. Melanoma cells produce melanin, which causes the melanoma to appear in varied shades of tan, brown and black. Sometimes it begins in or around the area of moles or other dark spots in the skin. It will spread if not diagnosed and treated early.
Another less common type of skin cancer is Merkel cell carcinoma. Merkel cell carcinoma forms on or just beneath the skin, usually in parts of the body that have been exposed to the sun. It is most common in older people and in people with weakened immune systems. Also called Merkel cell cancer, neuroendocrine carcinoma of the skin, and trabecular cancer.
Remember, not all changes in your skin are cancer, but you should see a doctor if you notice suspicious changes in your skin.
Please use the following links to access comprehensive skin cancer information provided by the National Cancer Institute from its PDQ® Database.
Learn more about nonmelanoma skin cancer...
Learn more about melanoma...
Learn more about Merkel cell carcinoma...