Aug. 8, 2017 -- A new report about colorectal cancer reveals an unexplained trend: Death rates are rising among white people under the age of 55 but dropping for African-Americans in the same age group.

“The rise is confined to whites, and that’s very surprising,” says the report’s lead author, Rebecca Siegel, the strategic director of surveillance information services at the American Cancer Society.

The Cancer Society report covers the years 1970 to 2014. It tracks changes in the death rate from colorectal cancer among people between the ages of 20 and 54, who have historically been less likely than older people to develop the disease. The report’s authors analyzed 242,637 deaths to reach their conclusions.

' } ); ss.positionArrowsIa('#dyn-ss-1', 0, slideshow_length); /* Attach event handlers */ $('#dyn-ss-1').find('.controls.primary .prev').on('click tap', function(event) { var currSlide = slideshowInst.getCurrentSlide(); event.preventDefault(); if(currSlide !== 0){ slideshowInst.goToPrevSlide(); wmdPageLink('ia-ss-ctl_prev'); } }); $('#dyn-ss-1').find('.controls.primary .next').on('click tap', function(event) { event.preventDefault(); slideshowInst.goToNextSlide(); wmdPageLink('ia-ss-ctl_next'); }); /* Reposition arrows when browser is resized */ $(window).on('resize', function() { var currentSlide = slideshowInst.getCurrentSlide(); // only run if width changed to prevent it triggering on iPhone scroll if (currentWidth !== $(window).width()) { currentWidth = $(window).width(); ss.positionArrowsIa('#dyn-ss-1', currentSlide, slideshow_length); } }); }, onSlideAfter: function ($slideElement, oldIndex, newIndex) { ss.positionArrowsIa('#dyn-ss-1', newIndex, slideshow_length); } } ); }); }); });

In 1970, 6.3 out of 100,000 people under 55 died from the disease. That rate dropped to 3.9 by 2004. That’s when it started to climb among white people. Over the next 10 years, their death rate increased from 3.6 to 4.1 out of 100,000.

It’s a much different story for young African-Americans. Their death rate has remained higher than that of whites, but it has continued to slowly and consistently decline, from 8.1 per 100,000 in 1970 to 6.3 in 2014.

“Death rates are the gold standard for progress against cancer,” says Siegel. “If you have declining death rates for cancer, it’s always a good thing.”

Cleveland Clinic colorectal cancer specialist James M. Church, MD, says he thinks improved access to care for African-Americans helps explain the continuing drop in deaths.

“Care has been changing and improving,” he says.

Siegel agrees.

"Declines in blacks are due primarily to improvements in treatment for [colorectal cancer], which very likely attenuated the rise in whites.

"Also of note, in 2015 alone -- the most recent year for which we have mortality data -- there were more than 6,600 [colorectal cancer] deaths in people younger than 55 years in the U.S. -- 6,606 to be exact," she says.

Darrell M. Gray II, MD, a gastroenterologist at Ohio State University Comprehensive Cancer Center, says researchers don't know what's behind the change in mortality rates.