MIAMI - When African-American and Hispanic blacks are diagnosed with malignant melanoma, it's more often at an advanced stage than when it is diagnosed in whites, researchers here have found.
MIAMI, June 19 - African-Americans and Hispanic blacks are at lower risk than whites for melanomas, but the disease tends to be more advanced when blacks are diagnosed, University of Miami researchers reported.
Among Miami-Dade county residents diagnosed with melanoma over five years, a third of Hispanic black patients and half of African-American blacks had advanced regional or metastatic disease at the time of diagnosis, compared with only 16% of non-Hispanic whites, reported Robert S. Kirsner, M.D., Ph.D., and colleagues, in the June issue of Archives of Dermatology.
The rate of melanoma is about 20 times higher among whites than African-Americans, and five times higher among whites than Hispanics, but both Hispanic and non-Hispanic blacks remain susceptible to melanoma. They may not be aware of it, however, because most prevention efforts are targeted toward those most at risk, such as blue-eyed, fair-haired whites.
"Although varying cultural values may account for some differences in health care use, public education regarding melanoma risk in black and Hispanic persons and delivery of skin cancer screening and examinations represent the main potential areas of intervention to improve the stage at diagnosis of melanoma in these populations," the investigators wrote. "We hope that earlier diagnosis of melanoma at a more favorable stage will ultimately improve melanoma survival rate in minority populations."
The authors looked at data on a total of 1,690 cases of melanoma reported in Miami-Dade between 1997 and 2002 in which the race or ethnicity of the patient, or both, and the diagnosis was recorded.
Of these cases, 1,176 (70%) occurred in non-Hispanic whites, 485 (29%) occurred in Hispanics blacks, and 29 (2%) were seen in African-American blacks.
When the data were broken down by stage at diagnosis, the investigators found that in situ melanomas occurred most frequently among non-Hispanic whites, accounting for 27% of all tumors in this group, compared with 10% of all tumors in non-Hispanic black patients, and 22% in Hispanic black patients.
In addition, while more than half of all Hispanics blacks and whites had local-stage tumors at diagnosis (57% and 52%, respectively), and only 38% of African-ancestry patients had localized disease.
"In contrast, non-Hispanic blacks had the highest percentage of late-stage diagnosis: 52% were diagnosed as having either regional or distant-stage melanoma," the authors wrote. "The percentage of Hispanic patients with regional- or distant-stage melanoma was also higher than that for non-Hispanic whites: 26% compared with 16%,"
They acknowledged that the study is limited by the difficulty of ascertaining ethnicity when patients do not provide the information themselves, especially among women who may marry into Hispanic families and take a Spanish-sounding surname.
Looking at melanoma rates by race or ethnicity, or both, also does not take into account variations in skin pigmentation. In addition, the tumor registry data used in the study did not include information about tumor depth, they noted.
Limitations aside, the data, particularly those concerning the disparity between non-Hispanic whites and Hispanics, are of particular concern, the authors noted:
"Despite the persistent increase in melanoma incidence among Hispanic persons, melanoma survival in this population has not improved to the same degree as that in white individuals," they wrote. "The five-year cause-specific survival rate of melanoma is 77.1% for white Hispanic men and 86.8% for white Hispanic women compared with 86.5% in non-Hispanic white men and 92.2% in non-Hispanic white women. The gap in melanoma stage at diagnosis likely contributes to differences in survival."
The findings also point to inadequate secondary prevention and screening programs for blacks and Hispanics, and suggest a need for increased public awareness of the threat melanoma poses to people of all skin colors.
"The delayed diagnosis of melanoma in Hispanic and black individuals could also reflect lower skin cancer awareness," they wrote. "Understandably, darker-skinned individuals perceive themselves at either low or no risk for melanoma because much of the public education efforts have targeted the white populations, especially those with blue eyes and blond or red hair."