Tuesday, August 5, 2008

Melanoma: its misconceptions leading to late diagnosis and high mortality rates

With the incidence of skin cancer on the rise, it has never been more important for the public to practice the prevention and detection steps that are key to avoiding melanoma, the most deadly form of skin cancer.

Yet in the case of African- Americans, detection may be more difficult because studies of African-Americans who are diagnosed with melanoma have shown that the condition most often develops on non-sun-exposed areas of the body.

This finding along with the misconception that melanoma is not a significant threat for individuals with darker skin, may contribute to the higher rates for this population. Prevention and detection messages about melanoma are not being heeded by African- Americans.

Melanoma is the deadliest form of skin cancer and is one of the few cancers where the cause is known- overexposure to the ultraviolet rays of the sun and artificial light, like those in a tanning bed.

One reason why African- Americans are not overly concerned about melanoma is that most of the skin cancer warning messages are geared toward fair-skinned individuals with blue eyes and blond or red hair who sunburn easily.

Also, the incidence of me-lanoma in African-Ameri-cans is much lower than in Caucasians due to the additional melanin, or pigment, in the skin. While this pigment offers some sun protection, dark brown or black skin is not a guarantee against melanoma.

However, once African-Americans are diagnosed with melanoma, studies have shown that their long-term survival is significantly lower than that of Caucasians, 58.8 percent compared to 84.8 percent.

Melanoma has a 96 percent cure rate when detected early, yet the mortality rate in African-American patients remains high and can be directly linked to the advance state of the disease at the time of diagnosis." The question is why are African-American patients waiting so long to seek treatment?

When diagnosed, mela-noma in African-American patients has often spread to other parts of the body. Melanoma in these advanced stages is usually fatal.

It is still unclear if racial differences in melanoma mortality are related to delays in diagnosis and medical treatment, or it represents inherent differences in the aggressiveness of the disease in the skin of people of colour.

Another factor that may prevent African-Americans from seeking early treatment is that they usually develop melanoma in locations that differ from those described in conventional detection messages.

A recent study showed that while 90 percent of Caucasian patients develop melanoma on skin that is regularly sun-exposed, only 33 percent of African-American patients developed the condition in these areas.

In African-Americans, melanoma most often develops on non-sun-exposed skin, such as the foot, toenails and the mucous membranes of the mouth, nasal passages or genitals.

Another challenge that may delay treatment is that melanoma of the nails, which peaks in incidence between the ages of 50 and 70 in African-Americans, often does not conform to the ABCD rule of pigmented lesions – "A" being asymmetry; "B" being border irregularity; "C" being colour variations; and "D" being diameter larger than six mm.

The ABCD rule is the best way to determine if a suspicious mole or spot on the body is changing and requires immediate medical attention."

African-American also should examine their nails for some additional symptoms that can signal a serious condition."

These additional factors are most commonly found on the nails of the thumbs or big toes and may include brown or black bands under the nail, and a spot that extends into the nail folds or the skin that supports the nail.

It is important for African Americans and their physicians to know that melanoma can and does occur in people of colour, and a greater effort needs to be made to inform these audiences about this

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