Equal-opportunity melanoma

Key Points

Miami - Less is known about the incidence of melanoma and its diagnosis in Hispanic populations than in other groups in the United States, though it does appear clear that anomalies exist.

Given its large Hispanic population (61 percent) and the association between latitude and exposure to ultraviolet radiation, Miami-Dade county in Florida is a prime location for the study of incidence and diagnostic trends in Hispanic populations.

Robert S. Kirsner, M.D., Ph.D., professor and vice chairman, department of dermatology and cutaneous surgery, University of Miami Miller School of Medicine, Miami, mined data from the Florida Cancer Data System for Miami-Dade County for the period 1997 through 2002 to study these questions.

The study identified 1,176 non-Hispanic whites, 29 non-Hispanic blacks and 485 Hispanics of all races who were conclusively diagnosed with melanoma.

It found rates of initial diagnosis at the in situ stage of 27 percent, 10 percent and 22 percent for each study group, respectively. Metastasized melanoma was diagnosed at rates of 9 percent, 16 percent and 31 percent.

"We found that blacks and Hispanics both were diagnosed at a later stage of melanoma than white patients," Dr. Kirsner says.

Those findings are consistent with what smaller, earlier studies have found among the three populations.

Dr. Kirsner says, "This study is important because there is less work on Hispanics, and they are an increasing percentage of the total U.S. population," now accounting for some 12.5 percent, overall.

"It may be that melanoma in blacks and Hispanics is a different animal, that it is more aggressive and that is why it is diagnosed later," he says. "But we think it is more of a public health issue, that blacks and Hispanics, and perhaps physicians as well, don't realize that while they are at lower risk for melanoma, they are not immune to it, they can still get melanoma."

Dr. Kirsner says, with males, a spouse is more likely to be the first to recognize a lesion that subsequently is diagnosed as melanoma, whereas with females, the initial recognition it is more likely to be made by a healthcare provider.

While differences in family structure or the role of immigration may be factors contributing to these different outcomes between ethnicities, more significant factors likely are the level of knowledge regarding the deadly nature of melanoma, and access to healthcare, which correlates with lower socioeconomic status and minority status.

Sites less traveled ...

Dr. Kirsner tells Dermatology Times that the locations of melanoma tend to be a little different in blacks and Hispanics than in whites.

"Blacks tend to have melanoma on the palms and soles," but this doesn't exclude a role for ultraviolet light, as "some data suggests that ultraviolet light has a systemic effect and can manifest itself distant from the site that was exposed to the sunlight."

Dr. Kirsner believes, "At the very least, these findings mean that we should reevaluate and expand the public health message on melanoma to nonwhite populations. Whether it is cost-effective to expand screening for melanoma in these populations is not clear."

While melanoma is more common in older persons, "It can occur in young adults. In whites, it is the second-most-common cancer in both men and women under the age of 40. That is one of the reasons why it has such a high cost to society."

He says, "We are doing better overall with public education and screening in white populations; we are catching melanoma earlier."