SignatureMD Minutes: Skin Cancer
Skin cancer is the most common type of cancer in the United States. An estimated 40 to 50 percent of Americans who live to age 65 will have skin cancer at least once. The most common skin cancer is basal cell carcinoma, which accounts for more than 90 percent of all skin cancers in the United States. The most virulent form of skin cancer is melanoma. In some parts of the world, especially in Western countries, the number of people who develop melanoma is increasing faster than any other cancer. In the United States, for example, the number of new cases of melanoma has more than doubled in the past 20 years.
Three types of skin cancer are the most common:
Basal cell carcinoma is a slow-growing cancer that seldom spreads to other parts of the body. Basal cells, which are round, form the layer just underneath the epidermis, or outer layer of the skin. Squamous cell carcinoma spreads more often than basal cell carcinoma, but still is considered rare. Squamous cells, which are flat, make up most of the epidermis.
Melanoma is the most serious type of skin cancer. It occurs when melanocytes, the pigment cells in the lower part of the epidermis, become malignant, meaning that they start dividing uncontrollably. If melanoma spreads to the lymph nodes it may also reach other parts of the body, such as the liver, lungs or brain. In such cases, the disease is called metastatic melanoma.
Both basal and squamous cell cancers are found mainly on areas of the skin that are exposed to the sun – the head, face, neck, hands and arms. However, skin cancer can occur anywhere.
For melanoma, the first sign often is a change in the size, shape, color or feel of an existing mole. Melanomas can vary greatly in the way they look, but generally show one or more of the “ABCD” features:
Their shape may be Asymmetrical.
Their Borders may be ragged or otherwise irregular.
Their Color may be uneven, with shades of black and brown.
Their Diameter may change in size.
Ultraviolet (UV) radiation from the sun is the main cause of skin cancer, although artificial sources of UV radiation, such as sunlamps and tanning booths, also play a role.
The risk is greatest for people who have light-colored skin that freckles easily – often those who also have red or blond hair and blue or light-colored eyes – although anyone can get skin cancer. About 10 percent of all patients with melanoma have family members who also have had the disease.
Mohs Surgery named after Dr. Frederick Mohs who perfected the techniques in the 1930s is used extensively for Basal Cell and Squamous cell tumors. Mohs differs from other techniques in that microscopic examination of all excised tissues occurs during rather than after the surgery, thereby eliminating the need to “estimate” how far out or deep the roots of the skin cancer go. This allows the Mohs surgeon to remove all of the cancer cells while sparing as much normal tissue as possible. In this way, Mohs surgery eliminates the guesswork in skin cancer removal, producing the best therapeutic and cosmetic results.
In the case of melanoma initial treatment with a broad excision is the treatment of choice to make sure all melanoma cells are eliminated. The best treatment is prevention as Ben mentioned earlier and surveillance to find skin cancers at the earliest possible time. Monthly self examination and yearly dermatological exams are highly recommended.