The method to screen for colorectal cancer has been in use in clinical trials for several years but a study published in this week's New England Journal of Medicine says it identified nine out of 10 people who had cancers and large growths seen by regular colonoscopies.
The American College of Radiology Imaging Network (ACRIN) trial, sponsored by the National Cancer Institute, was conducted at UCLA and 14 other sites. It is the largest multicenter study to estimate the accuracy of state-of-the-art CT colonography. UCLA enrolled more than 150 participants in the study, with more than 2,600 volunteers participating nationwide.
The trial evaluated CT colonography findings using conventional colonoscopy as the reference standard. The results showed virtual colonoscopy was highly accurate in finding moderate to large polyps, which are unusual growths that could be cancerous or precancerous, and even very small polyps were detected with high sensitivity.
While a standard colonoscopy uses a long, flexible tube with a camera that is threaded through the colon, the virtual colonoscopy uses three-dimensional images that are viewed as a video of the inside of the colon and permit a thorough and minimally invasive evaluation of the colorectal structure.
The test can also be carried out on a section of people who cannot have complete, regular colonoscopies because they have abdominal lesions or a very twisted colon. It is carried out using a thin tube inserted in the rectum.
Colorectal cancer is the third most frequently diagnosed cancer and the second leading cause of cancer death in men and women in the U.S. Doctors recommend that adults age 50 and older receive a colonoscopy every 10 years.
