Skin cancer is a tumor within the skin. The American Cancer Society reports that non-melanoma skin cancer is the most prevalent type of cancer in the United States, occurring in more than 1 million people annually. Those with fair skin are at greater risk of developing skin cancer than darker skinned individuals. Basal, squamous, and melanoma are the primary examples of skin cancer.
Basal Cell Carcinoma
This skin cancer is the most common type, with over 800,000 Americans diagnosed each year, states Merck Manuals Medical Library. Also called rodent cell carcinoma, it begins in the cells at the basal layer of the skin. It is slow growing and seldom spreads to other parts of the body, although it can invade the surrounding tissues. Basal cell skin cancer has the appearance of a small, shiny, flat, red plaque, or papule. The cancer is most often seen on sun-exposed areas like the head, neck, face and backs of the arms and hands.
Squamous Cell Carcinoma
The squamous cell type is a malignant tumor, usually located on sun exposed areas. It can develop in normal skin, or it might arise from a scar or other lesion. Squamous cell cancer often appears as a hard, red, raised area that flakes or crusts. When detected early this cancer is almost always curable. Left untreated, the growth can advance into the surrounding skin and underlying tissue. Uncommonly, sqaumous cell cancer spreads to more distant parts of the body, starting with the lymph nodes.
Melanoma is a cancerous growth beginning in the pigment producing cells, or melanocytes. Malignant melanoma is the most dangerous of all skin cancers, resulting in over 8,000 deaths each year, according to the American Academy of Dermatologists. The growths often start in or near an existing mole but can arise from other areas of the skin. They can also occur on the mucous membranes of the eyes, mouth or genitalia. Melanomas generally display a mix of brown, black, blue and tan shades. However, they can also be white or red. With early detection, melanoma is usually curable. After the disease has spread to the lymph nodes, treatment is more difficult, with 5-year survival rates of 25 to 70 percent.
About this Author
Kalli Harrison is a naturopathic physician living in Portland, Ore. She graduated from National College of Naturopathic Medicine in the year 2000, and also holds a degree as a medical laboratory technician. Dr. Harrison has been writing health and medical information for patients and clients for more than 10 years.