Children diagnosed with inflammatory bowel diseases have a higher risk for developing cancer later in life. Photo by www_slon_pics/Pixabay
March 1 (UPI) -- Children diagnosed with inflammatory bowel diseases such as Crohn's and ulcerative colitis are more than twice as likely to develop cancers later in life compared with those who do not have IBD, an analysis published Tuesday by JAMA Network Open found.
In the review of data from five studies with nearly 20,000 participants collectively, the risk for cancer among people diagnosed with inflammatory bowel diseases as children was 2.4-fold higher than for those who did not have these common digestive diseases, the data showed.
Those with Crohn's disease as children were about twice as likely to develop cancer as adults, while those with ulcerative colitis in childhood were 160% more likely to be diagnosed with cancer later in life, the researchers said.
Liver, colon and rectal and small bowel cancers were the most common among those diagnosed with inflammatory bowel diseases as children, they said.
"The risk of cancer among individuals diagnosed with IBD in childhood is two-fold increased and primarily explained by an increased risk of gastrointestinal cancers," study co-author Dr. Tine Jess told UPI in an email.
It is believed that "chronic ongoing inflammation, both locally in the gut and systemically, [caused by IBD], may increase the risk of cancer," said Jess, a professor of clinical medicine at Aalborg University in Denmark.
IBD is actually a group of inflammatory conditions of the colon and small intestine that includes Crohn's disease, which affects the small and large intestine, and ulcerative colitis, which affects the colon and rectum.
The cause of the inflammation behind these conditions remains unknown, but it is believed to be related to problems with the immune system, the agency says.
IBDs, which cause symptoms such as persistent diarrhea, abdominal pain, rectal bleeding and bloody stools, weight loss and severe fatigue, are far more common in adults than in children, the Centers for Disease Control and Prevention reports.
Some 3 million adults and less than 60,000 children age 17 years and younger in the United States have been diagnosed with these diseases, the CDC estimates.
However, IBDs are becoming more common in children, and with longer exposure to the effects of these diseases on the digestive tract, young people may see more intestinal damage, which in turn may increase their risk for certain cancers, Jess and her colleagues said.
Among children in the studies included in this analysis, the risk for liver cancer was 55 times higher for those with IBDs in childhood compared with their healthy peers, the data showed.
The risk for colon and rectal cancers was about 20 times higher, while the risk for small bowel cancer was about 16 times higher, the researchers said.
Still, the overall risk for cancer among all children in the included studies was small, they said.
"Cancer is rare among children and young individuals in general -- [hence] the relative risk estimates easily appear high," Jess said.