Racial cancer mortality gap narrows, but breast, prostate cancer gaps remain

The gap in cancer mortality between Black and White individuals has narrowed substantially since its peak in the early 1990s, with lung and prostate cancer accounting for more than half of the improvement among men, according to a study published in JAMA Oncology by researchers at the American Cancer Society.

How the study was conducted

The study drew on cancer mortality data compiled by the National Center for Health Statistics for non-Hispanic Black and non-Hispanic White individuals who died of cancer between 1991 and 2023 in the 50 states and the District of Columbia.

Using SEER*Stat software, the authors compared excess mortality rates — a measure of how many more cancer deaths occurred among Black individuals than would be expected if they died at the same rate as White individuals — between a peak period (1991-1995) and a contemporary period (2019-2023). Mortality rates were age-standardized and calculated as five-year moving averages across 30 individual cancer types to improve estimate stability, particularly for less common cancers. The analysis covered 2,461,715 cancer deaths in the earlier period and 2,674,385 in the more recent one.

Lung and prostate cancer drove the narrowing gap

The all-cancer excess mortality rate fell from 124.0 to 25.6 per 100,000 among Black males and from 34.2 to 12.5 per 100,000 among Black females, the study found, declines of 98.4 and 21.7 per 100,000, respectively. Among men, lung cancer accounted for the largest share of that improvement (31.1%), followed by prostate cancer (25.8%) and esophageal cancer (12.1%).

Among women, colorectal cancer contributed the most (18.8%), followed by cervical cancer (16.9%) and lung cancer (15.1%). The mortality rate ratio between Black and White individuals also narrowed, from 1.47 to 1.14 among men and from 1.20 to 1.10 among women.

Where breast, prostate and uterine cancer disparities remain

Despite the overall progress, prostate, lung and stomach cancer remained among the top five cancer types with the largest excess mortality among Black men in 2019-2023, and colorectal cancer climbed from fifth to second place in that ranking while liver cancer rose from 10th to fifth. Among women, breast cancer continued to account for the greatest excess mortality (7.2 per 100,000), followed by uterine corpus cancer (4.9 per 100,000), whose disparity widened over the study period even as most other cancer types improved. Relative disparities for breast cancer widened from 22% to 37% and for uterine corpus cancer from 82% to 102% between the two periods, according to the study.

“Despite meaningful contributions from smoking prevention, expanded screening, and improved access to treatments, mortality gaps between Black individuals and White individuals persist across both common and rare cancer types, indicative of the continuing effects of disparities rooted in broader social determinants of health,” the study authors wrote. “As a legacy of slavery and subsequent discriminatory policies, disparities in poverty and education function as interconnected upstream determinants of cancer outcomes.”

How screening and insurance coverage may impact outcomes

The study noted that Black individuals were 53% less likely than White individuals to receive lung cancer screening between 2017 and 2020 and 33% less likely to receive follow-up care between 2012 and 2018. Racial differences in prostate-specific antigen (PSA) screening prevalence also widened after the US Preventive Services Task Force recommended against routine PSA screening in 2012, with screening rates among Black men falling from 30.3% to 18.7% by 2018, a steeper decline than among White males. However, recent research suggests it would be beneficial to implement screening guidelines that are tailored to Black males, including earlier and annual screening.

“Large-scale clinical trials with greater representation of Black males would further strengthen the evidence base needed to promote USPSTF guideline revision,” the authors wrote. “Also, despite comparable survival under equal access settings, population-based studies continue to show lower survival among Black patients, with lower treatment receipt and longer delays from diagnosis to treatment identified as major barriers.”

The authors also cited prior research estimating that closing the insurance coverage gap alone could narrow survival disparities by about 50% in colorectal cancer and by one-third in early-stage breast cancer.

“Persistent or worsening disparities in breast cancer and uterine corpus cancer and substantial residual disparities in prostate cancer highlight priorities for equitable interventions,” the researchers concluded, noting that the findings “may guide more targeted and efficient cancer prevention and control strategies to further accelerate progress.”

The study noted that Black individuals were 53% less likely than White individuals to receive lung cancer screening between 2017 and 2020 and 33% less likely to receive follow-up care between 2012 and 2018. Racial differences in prostate-specific antigen (PSA) screening prevalence also widened after the US Preventive Services Task Force recommended against routine PSA screening in 2012, with screening rates among Black men falling from 30.3% to 18.7% by 2018, a steeper decline than among White males.

The authors also cited prior research estimating that closing the insurance coverage gap alone could narrow survival disparities by about 50% in colorectal cancer and by one-third in early-stage breast cancer.

“Persistent or worsening disparities in breast cancer and uterine corpus cancer and substantial residual disparities in prostate cancer highlight priorities for equitable interventions,” the researchers concluded, noting that the findings “may guide more targeted and efficient cancer prevention and control strategies to further accelerate progress.”