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Cancer and Blood Care

Skin Cancer

Skin cancer is usually a result of too much sun exposure. Skin cancer is the most common form of cancer. Many types of skin cancer are both preventable and treatable. There are five different types of skin cancer:

Basal cell carcinoma is the most common form, accounting for 90 percent of all skin cancers. It starts in the basal cells, at the bottom of the outer skin layer. This skin cancer is caused by long-term exposure to sunlight. It is the most easily treated.

Squamous cell carcinoma is the second most common type of skin cancer. It starts in the outer skin layer, eventually penetrating the underlying tissue if not treated. It is easily treated when found early, but in a small percentage of cases, this cancer spreads to other parts of the body.

Malignant melanoma is the most serious type of skin cancer, and it is responsible for the most deaths. However, it can be cured if it is diagnosed and removed early. Melanoma starts in moles or other growths on normal skin.

Kaposi's sarcoma (KS) is caused by a virus in the herpes family. This aggressive AIDS-related form affects about one-third of people with AIDS. A more slow-growing form occurs in elderly men of Italian or Jewish ancestry.

Most skin cancers occur on parts of the body that are repeatedly exposed to the sun, including the head, neck, face, ears, hands, forearms, shoulders, back, lower legs and chests.

Skin Cancer Signs and Symptoms

Basal cell carcinoma:

  • Shiny bump that is pearly or translucent
  • Flat, flesh-colored lesion appearing anywhere on the body

Squamous cell carcinoma:

  • Hard, red nodule on face, lips, ears, neck, hands, arms
  • Flat lesion with scaly surface

Melanoma:

  • Change in color, size, shape or texture of a mole
  • Skin lesion with irregular borders
  • Growth of an existing skin lesion
  • Large brown spot with darker speckles
  • Hard, dome-shaped bumps anywhere on your body

The only way to know for sure whether a mole or spot on your skin is cancer is to have a doctor look at it.

Skin Cancer Causes

Exposure to ultraviolet radiation from the sun is the main cause of skin cancer. Skin cancer may also be due to genetics or radiation treatments. A virus causes Kaposi's sarcoma.

Who is Most at Risk?

People at risk for developing skin cancer may have the following conditions or characteristics:

  • Fair skin
  • Spend a lot of time outdoors in work or leisure activities
  • History of sunburn
  • Family history of skin cancer
  • Many moles, freckles or birthmarks
  • Are over age 40
  • Large dark-colored birthmark, known as congenital melanocytic nevus
  • Pre-cancerous skin lesions, such as actinic keratosis
  • HIV-positive -- a specific risk for Kaposi's sarcoma
  • Being in the sun a lot as a child