U.S. cancer deaths have trended downward for decades, but the pace of improvement varies markedly by place.

A new study published in the British Journal of Cancer examined nearly three thousand counties from 1981 through 2019, using death certificates and data that cover more than twenty one million cancer deaths gathered through the Wide-Ranging Online Data for Epidemiologic Research system.

The work came from Mississippi State University’s Social Science Research Center in collaboration with Oak Ridge National Laboratory.

Researchers mapped how mortality improved over time and found that, while the national count shows progress, the gains were not shared equally across geography and income levels.

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Across the country, the overall trajectory tells a cleaner tale, yet regional patterns reveal a stubborn divergence.

Urban coastal counties and wealthier regions consistently showed larger declines in cancer mortality and bigger reductions in excess deaths than inland and poorer areas.

“In a complex nation such as the U.S., we should not be too surprised that there are large differences in health outcomes shaped by the diversity and variety of local regions and groups,” Arthur G. Cosby, the study's lead author, said.

“Cancer improvement over the last few decades certainly aligns with this perspective,” he said.

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By 2019, the gap in progress widened further. The top ten percent of highest income counties experienced roughly seven times greater mortality improvement than the lowest income counties.

The study highlighted that the largest gains were concentrated along the Atlantic and Pacific coasts, while rural and interior communities tended to show more modest progress.

“The magnitude of the mortality differences between coastal and inland regions, [and] the large differences between places with different income levels and rural/urban places, were larger than I anticipated,” Cosby said.

“The link between improving health and increasing disparities is poorly understood. I am pursuing that question now,” he added.

Researchers noted that declines in tobacco use and improvements in screening and treatment likely contributed to the overall trend.

Wealthier metropolitan areas have often pursued aggressive tobacco control policies that help explain some of the disparities in cancer mortality.

“Wealthy, metropolitan New York City has been aggressive in instituting tobacco control measures, and the results show,” Cosby noted.

“Manhattan had a lung cancer rate of 49 per 100,000 in 1991. By 2019, it cut its rate to 19.6 — a 60% reduction.”

More aggressive screening campaigns, including at major medical centers, can diagnose pre-cancers or cancers earlier, Siegel, who was not involved in the study, said.

“There are many limitations associated with the use of death certificates in research, such as accuracy of cause of death, possible multiple causes and changes in medical explanation for death over time,” Cosby said.

Based on the findings, the authors urge more county level studies that account for regional variation and warn that the pace at which life saving interventions are adopted differs by place and could widen disparities even as most places improve.

“The varying speed of adoption of life-saving interventions between geographic places may produce increasing disparities,” Cosby said.

“It is possible to have a situation where nearly all places are improving their cancer mortality, but at much different rates.”