For the first time, a study has shown that removing polyps by colonoscopy not only prevents colorectal cancer from developing, but also prevents deaths. Patients in the study were evaluated for up to 23 years after having the procedure, providing the longest follow-up results to date. “Our findings provide strong reassurance that there is a long-term benefit to removing these polyps and support continued recommendations of screening colonoscopy,” says Memorial Sloan-Kettering biostatistician Ann G. Zauber, the study’s lead author. Tumor-like growths called adenomatous polyps are the most common abnormality found during colonoscopy screening and have the potential to become cancerous. Previous research has showed that removal of polyps prevented colorectal cancer but it was not known whether the cancers were potentially lethal. This study assessed whether removal of polyps reduced colorectal cancer mortality -- indicating that the polyps removed had the potential to cause cancer death.