Melanoma on scalp, neck most deadly, study finds
By Will Dunham
WASHINGTON (Reuters) - Melanoma, the most dangerous form of skin cancer, is much deadlier when it appears on the scalp or neck than somewhere else on the body, according to a study published on Monday.
People with scalp or neck melanomas died at nearly twice the rate of those with melanoma elsewhere on the body, the researchers at the University of North Carolina at Chapel Hill found. People with melanomas on the arms, legs, face or ears were found to have the best prognosis.
They analyzed data on 51,704 people diagnosed with melanoma in the United States from 1992 to 2003, and found that survival rates varied depended on where on the body it first appeared.
"Melanoma is a skin cancer that is derived from the pigment cells in the skin. It's the most deadly type of skin cancer. It can metastasize (spread to other parts of the body) early when the lesions are still quite small," Dr. Nancy Thomas of the UNC School of Medicine and Lineberger Comprehensive Cancer Center, said in a telephone interview.
Thomas said part of the reason for the deadliness of melanoma on the scalp and neck may be that diagnosis may be delayed because it can be obscured by hair on the scalp.
But that probably is not the only explanation -- and these melanomas for a variety of reasons may be more aggressive than those appearing somewhere, Thomas said. For example, these people are more likely to have cancer that spreads to the brain than those with melanoma on their arms, legs or trunk.
The study placed the five-year survival rate for people with scalp or neck melanomas at 83 percent, compared with 92 percent for those with melanomas elsewhere on the body. The 10-year survival rate for people with scalp or neck melanomas was 76 percent, compared to 89 percent for other melanomas.
"This finding has implications for screening and public health recommendations, and we urge physicians, physician assistants, nurses and nurse practitioners to examine the scalp/neck carefully during routine skin examinations," the researchers wrote in the journal Archives of Dermatology.
Melanoma is the leading cause of death from skin disease. Melanoma is less common than other kinds of skin cancer, but its rates have been increasing. The first sign of melanoma often is a change in the size, shape or appearance of a mole.
Melanoma can be linked to sun exposure, especially sunburns during childhood. People with fairer skin are at elevated risk, and some people have a family history of melanoma.
The study showed that 43 percent of the people in the study had melanomas on their arms or legs, 34 percent on the trunk, 12 percent on the face or ears, 6 percent on the scalp or neck and 4 percent at an unspecified site.
Thomas said that while only 6 percent of people with melanoma have it on their scalp or neck, they accounted for 10 percent of all melanoma deaths.
People with scalp or neck melanomas tended to be older than those with other melanomas -- age 59, compared to 55 for the others -- and more likely to be men, the researchers said.
The American Cancer Society estimates about 8,400 people will die of melanoma in the United States this year and there will be about 62,000 new cases.
(Editing by Maggie Fox)