Now, a new study finds that not only are cases increasing, but deaths from colorectal cancer are also on the rise in this age group.
"This indicates that the increase in incidence is not exclusively due to more colonoscopy use and increased detection, but a true increase in disease occurrence that is of sufficient magnitude to outweigh improvements in survival that have occurred in all age groups because of better treatment", Siegel said. African Americans on the other hand, actually saw a slight decline in those death rates over the same period.
The mortality rate for whites had been declining for decades, but it began to climb starting in 2004, going from 3.6 per 100,000 to 4.1 per 100,000 in 2014.
For several years, rates of colorectal cancer have been rising among Americans aged below 55.
The increase occurred only in white individuals, whose mortality rates increased by 1.4% (95% CI, 1.1-1.8) annually, from 3.6 per 100,000 in 2004 to 4.1 per 100,000 in 2014. For blacks, it went down to 6.1 per 100,000 in 2014.
According to a new study from the American Cancer Society, colon and rectal cancer deaths are rising for young adults, under the age of 50- just when you're supposed to start getting screenings.
A representative of American Cancer Society did not immediately return International Busines Times' request for comment.
The report was published August 8 in the Journal of the American Medical Association. But it should create "a sense of urgency and responsibility not to ignore signs that might indicate colon cancer". However, ACS noted that obesity is a risk factor that is universally increasing.
"Delayed initiation of screening is likely behind these lower rates, as well as other barriers like insurance coverage, which is lower in ages 50 to 54 years than older adults because of the universal coverage offered by Medicare beginning at 65 years", Siegel said.
Preventative colonoscopy exams have led to a decline in colon cancer cases, but some studies suggest that preventive exams don't necessarily help to stop colorectal cancer in its tracks. In contrast, the mortality rates for blacks in their 50s has declined since 1993.
This surge in colorectal cancer deaths was particularly surprising since, for decades, screening has been recommended for those 50 years old and up.
While research is ongoing to look into what may be causing this, experts believe the answer may lie at least partly in the microbiome - the bacteria that normally thrive in the body.
In the meantime, she emphasizes that while the overall risk of colorectal cancer in young and middle aged adults is still very small, there are preventive steps doctors and patients can take to protect themselves.
The important thing for now is to catch the cancer early on.
Symptoms of colorectal cancer include pain in the abdomen, bloody stool, constipation, weight loss, and change in bowel patterns.