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Nonmelanoma Skin Cancer vs. Melanoma


Nonmelanoma skin cancer is the most common form of skin cancer. There are about 1.3 million cases each year in the United States. Basal cell carcinoma (80%) and squamous cell carcinoma (16%) are the most common forms of nonmelanoma skin cancers, accounting for about 96% of all new cases of skin cancer.

Other nonmelanoma skin cancers account for less than 1% of nonmelanoma skin cancers, according to American Cancer Society. These less common skin cancers include:

  • Kaposi's sarcoma, which usually starts within the deeper layers of the skin but can also form in internal organs. The tumors consist of bluish-red or purple lesions. This cancer occurs in people with compromised immune systems such as those with HIV infection or AIDS as well as transplant recipients who are on immune-suppressing drugs.
  • cutaneous lymphoma, a type of lymphoma that begins in the skin.
  • skin adnexal tumors, rare tumors that start in the hair follicles or sweat glands, and are usually benign.
  • sarcomas, which usually start in tissues deep beneath the skin, but can develop in the skin as well.
  • Merkel cell carcinoma, a rare cancer of neuroendocrine origin that develops on or just beneath the skin and in hair follicles. These cancers usually appear as firm, reddish/purple shiny skin lumps.

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Melanoma is the least common, but most aggressive of the two types of skin cancer. Melanoma originates in melanocytes-the cells in the skin that produce pigment or melanin.

In 2004, there will be about 95,880 new cases of melanoma diagnosed in the United States--about 4% of all diagnosed skin cancers--but it accounts for about 77% of skin cancer deaths, according to the ACS. One person dies of melanoma every hour.

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Updated: May 4, 2007
This information is for educational purposes only and is not intended to replace the advice of your doctor or health care provider. We encourage you to discuss with your doctor any questions or concerns you may have.
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