Advanced young-onset adenoma increases colorectal cancer risk

Advanced young-onset adenoma (YOA) increases the risk for new colorectal cancer (CRC) eightfold, according to a study published online in the September issue of the American Journal of Gastroenterology.

Yas Casey, M.D., from the VA Loma Linda Healthcare System in California, and colleagues compared the risk for incident and fatal CRC in adults aged younger than 50 years with YOA diagnosis versus those with a normal colonoscopy. The analysis included 54,284 U.S. veterans (aged 18 to 49 years) who received a colonoscopy between 2005 and 2016.

The researchers found that cumulative 10-year CRC incidence was 0.11 percent after any adenoma diagnosis, 0.18 percent after advanced YOA diagnosis, 0.10 percent after nonadvanced adenoma diagnosis, and 0.06 percent after normal colonoscopy. Incident CRC risk was eightfold higher in veterans with advanced adenoma versus those with normal colonoscopy (hazard ratio, 8.0). No differences in fatal CRC risk were seen across groups.

"Cumulative CRC incidence and mortality at 10 years among individuals with either young onset nonadvanced or advanced adenoma diagnosis were both relatively low," the authors write.