The number of diagnosed cases of melanoma has been on the rise over the years but a recent British study reports that the "the epidemic may be due to diagnostic drift."

The report defines diagnostic drift as "the growing tendency to identify and treat benign lesions as malignant cancers," the New York Times reports.

"The study, published in the September issue of The British Journal of Dermatology, examined a cancer registry with 3,971 cases of melanoma and found that incidence increased 48 percent from 1991 to 2004, similar to the 44 percent increase reported by the Centers for Disease Control and Prevention over the same period for American whites. The disease is almost 20 times as common in whites as in blacks."

However, the research group found that almost all of the increase in diagnoses was in the earliest stage of the disease.

 “A lot of dermatologists will argue that they’re getting better at diagnosing melanoma, but I don’t think that’s very likely,” Dr. Marianne Berwick, a professor at the University of New Mexico said in the New York Times. “They’re taking a lesion that would not be diagnosed as melanoma 20 years ago and calling it melanoma.”

To read the full article and the implications of "diagnostic drift," click here: http://www.nytimes.com/2009/09/29/health/29mela.html?scp=20&sq=September+29+2009&st=nyt