African Americans Have a Higher Cancer Mortality Rate than African Immigrants, Experts Find

A study led by public health researchers at Sylvester Comprehensive Cancer Center at the University of Miami Miller School of Medicine found that Black immigrant populations in the U.S. showed lower cancer mortality than both African Americans and Whites. The results published in the journal Cancer Epidemiology revealed a complex interplay between genetic and environmental factors, evident even for cancers with relatively high mortality among all African-descendant groups.

“When examining cancer patterns, aggregating Black populations in the U.S. masks important cancer differences,” said the study’s lead author, Paulo S. Pinheiro, M.D., Ph.D., M.Sc., professor of public health at the Miller School of Medicine. “In turn, this hinders our global understanding of how race impacts cancer.”

In the study, researchers compared U.S.-born African Americans with African and Afro-Caribbean immigrants, a comparison that had never been undertaken on a population basis. The objective was to highlight specific cancer prevention and control needs, as well as to clarify global cancer epidemiology.

Co-authors of the study, published March 30, included experts from the Miller School Department of Public Health Sciences, the University of Nevada Las Vegas School of Public Health, Fox Chase Cancer Center’s Cancer Prevention and Control Program, and the American Cancer Society’s Surveillance and Health Services Research.

Researchers computed age-standardized cancer mortality rates for the most common cancers by using vital statistics from 2012 to 2017 from California, Florida, Minnesota and New York, states with diverse Black populations. Comparisons were made to the majority White population using mortality rate ratios.

Among Whites and Blacks in these four states, 707,426 cancer deaths occurred. Of the 83,460 Black decedents, 80 percent were African American (U.S.-born), while 20 percent were immigrants, including 12,422 Afro-Caribbeans and 1,658 Africans.

Lung cancer was the leading cause of cancer death for both White and African American males and females. Prostate and breast cancer were second, and colorectal cancer was third.

For Afro-Caribbean and West-Central African males, prostate cancer was the leading cause of cancer death. For East African males, liver cancer was the first. Breast cancer was the leading cause of cancer death among Afro-Caribbean, West-Central African, and East African females, followed by colorectal cancer for Afro-Caribbeans and East Africans. Endometrial cancer was the second cause of cancer death among West-Central Africans and third for Afro-Caribbean and East African females.

Of all deaths, African Americans had the highest combined mortality rates: 232 per 100,000 for males and 163 for females. Africans had the lowest all-sites-combined mortality rates: 121 and 99 per 100,000 for males and females, respectively, while Afro-Caribbeans were in the middle, at 140 and 106 per 100,000, respectively.

Researchers noted that their presentation and comparison of rates by specific cancer type for U.S.-born African Americans with African and Afro-Caribbean immigrants is novel. Moreover, their research shows that while some cancers point clearly to a genetic predisposition to more aggressive forms among all populations of African descent, such as prostate and endometrial cancer, in other cancers for which socio-environmental factors feature more prominently, such as lung, colorectal and breast, the study shows that African Americans have substantially higher rates than other Black populations.

To further explore the dynamic between socio-environmental and genetic risk for cancers among populations of African descent, researchers suggest additional, up-to-date studies in other countries with sizable Caribbean and/or Sub-Saharan African immigrant populations.

Written by Amanda Torres

Published on March 30, 2020