The outer layer of the skin (the epidermis) contains three kinds of cells. Most of those cells are squamous cells. Cells near the bottom of the epidermis are called basal cells. And cells that provide pigment (color) to the skin are known as melanocytes (pronounced MELL-uh-no-sites).
Each type of cell can become cancerous. The three types of skin cancers, therefore, are squamous cell cancer, basal cell cancer, and malignant melanoma (cancer of the melanocytes). Malignant melanoma is by far the most serious form of skin cancer.
Other forms of skin cancer occur, but they are quite rare. The most serious of these is Kaposi’s sarcoma (see Kaposi’s sarcoma entry). At one time, Kaposi’s sarcoma was very rare. It occurred primarily in older men of Mediterranean ancestry. It now occurs commonly in individuals with AIDS (see AIDS entry).
Exposure to sunlight is thought to be the major cause of skin cancers. About eight hundred thousand cases of squamous and basal cell cancers alone are diagnosed each year in the United States. The risk for skin cancers increases the closer one lives to the equator.
All forms of skin cancer begin with a single cell. For reasons that are usually not known, the cell begins to grow very rapidly. Its growth is soon out of control. It divides into two new cells, which continue growing wildly. Eventually the cancerous cells spread through a larger area. They can also begin to grow downward towards inner layers of the skin.
December 18th, 2009 at 1:24 am
The outer layer of the skin (the epidermis) contains three kinds of cells. Most of those cells are squamous cells. Cells near the bottom of the epidermis are called basal cells. And cells that provide pigment (color) to the skin are known as melanocytes (pronounced MELL-uh-no-sites).
Each type of cell can become cancerous. The three types of skin cancers, therefore, are squamous cell cancer, basal cell cancer, and malignant melanoma (cancer of the melanocytes). Malignant melanoma is by far the most serious form of skin cancer.
Other forms of skin cancer occur, but they are quite rare. The most serious of these is Kaposi’s sarcoma (see Kaposi’s sarcoma entry). At one time, Kaposi’s sarcoma was very rare. It occurred primarily in older men of Mediterranean ancestry. It now occurs commonly in individuals with AIDS (see AIDS entry).
Exposure to sunlight is thought to be the major cause of skin cancers. About eight hundred thousand cases of squamous and basal cell cancers alone are diagnosed each year in the United States. The risk for skin cancers increases the closer one lives to the equator.
All forms of skin cancer begin with a single cell. For reasons that are usually not known, the cell begins to grow very rapidly. Its growth is soon out of control. It divides into two new cells, which continue growing wildly. Eventually the cancerous cells spread through a larger area. They can also begin to grow downward towards inner layers of the skin.