Family cancer history raises colorectal cancer risk in IBD patients

A new Swedish study finds that people with inflammatory bowel disease (IBD) who have two or more close relatives with colorectal cancer are about 2.6 times more likely to develop the disease themselves, raising questions about current screening guidelines. The research, published in Gastroenterology, analyzed 124,387 IBD patients against 1.2 million people over a median of eleven years, during which 1,882 IBD patients developed colorectal cancer. This risk was significantly higher than the under 50 percent increased risk seen in patients with just one relative diagnosed before age 50. Current international guidelines focus on a first-degree relative diagnosed before age 50, but researchers suggest the number of affected family members may be a more important risk marker. The study also found that absolute cancer risk was similar for people with and without IBD who had affected relatives.