US Pharm. 2006;4:9.

The number of new melanoma cases in the United States is rising. The skin is the largest organ in the body. One in five Americans will develop skin cancer in his or her lifetime. Skin cancers are categorized as either nonmelanomas or melanomas.

Nonmelanomas
Nonmelanomas, usually basal and squamous cell cancers, are the most common skin cancers. Basal cell carcinoma occurs in the skin's upper layers and remains localized in the original site. Squamous cell carcinoma can spread locally and disseminate throughout the body. Both cancers are more common in individuals of fair complexion who have had significant sunlight exposure and are curable with early surgical removal.




Melanomas
Melanoma begins in the melanocytes. Because most of these cells continue producing melanin, melanoma tumors are often brown or black. Having a dark complexion lowers, but does not eliminate, the risk of melanoma. Melanoma is likely to spread to other parts of the body, but it is almost always curable in its early stages. Comprising 4% of all skin cancers, melanoma is much less common than basal and squamous cell skin cancers. However, it causes a large majority of skin cancer deaths. One person dies every hour from melanoma.

Men and women often develop melanoma on their upper back; women also commonly develop melanoma on their legs. Once melanoma spreads to the lymph nodes and through the bloodstream, there is no cure to treat the condition. Half of all melanomas are diagnosed in people under age 57. More young women die from melanoma than from any other cancer.

The American Cancer Society (ACS) estimates that about 62,190 new melanomas will be diagnosed in the U.S. during 2006. Among whites in the U.S. , incidence rates increased sharply at about 6% per year from 1973 until the early 1980s. Since 1981, however, the rate of increase slowed to about 3% per year.

About 7,910 deaths due to melanomas are expected during 2006. Since 1973, the mortality rate has increased by 50%. More recently, the death rate has leveled off for men and dropped slightly in women. Precaution and early diagnosis could prevent 100,000 new cases and 60,000 deaths in the U.S. , according to the ACS.

Risk Factors
The exact causes of melanomas are unknown, but certain risk factors are linked to the disease.
• Sun overexposure (UV sunlight or indoor tanning) is the greatest risk. Excessive sun exposure for the first 18 years of life increases risk.
• Fair-skinned persons have four times the risk of dark-skinned people; redheads and blondes have a two- to four-times greater risk than brunettes.
• People with numerous or atypical moles have a higher risk. Families with many moles in multiple generations have a greater risk.
• Family or personal history of melanoma elevates risk.
• People treated with medicines that suppress the immune system (e.g., transplant patients) have increased risk.

New Developments in Melanoma Treatment
Recently, scientists have discovered a gene mutation in many melanomas. This gene, BRAF, is an important discovery because doctors think that blocking the activity of this gene may be a useful treatment for people with advanced melanoma.

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