Compared with sigmoidoscopy, colonoscopy is more effective against advanced colorectal cancer
For average-risk adults, the value of the colonoscopy has remained largely uncertain, until now. In a new study, undergoing a colonoscopy was associated with an overall 70% reduction of advanced colorectal cancer (CRC) diagnoses, suggesting that colonoscopy is capable of detecting growths in both the left and right side of the colon before they become advanced-stage tumors.
Chyke Doubeni, MD, MPH, presidential associate professor of Family Medicine and Community Health at Penn Medicine, and lead author on the study said, “Our goal with this study was to understand the extent to which colonoscopy can prevent the diagnosis of advanced colorectal cancers, the ones that primarily result in death. What we saw was a dramatically reduced risk of death for patients who were screened.”
For the case-control study, researchers evaluated the medical records of 1012 average-risk patients between the ages of 55 and 85 years from 4 US managed care organizations that participate in the HMO Cancer Research Network. Among the 474 study participants diagnosed with advanced CRC, 251 of them (about 54%) presented with tumors in the right side of the colon, which sigmoidoscopy would have failed to detect.
Robert H. Fletcher, MD, MSc, professor emeritus at Harvard Medical School and coauthor on the study said, “The results of this study confirm the effectiveness of screening colonoscopy and reinforce the importance of the procedure for all adults over the age of 50.”
Study results are published online in the Annals of Internal Medicine.
Source: Perelman School of Medicine at the University of Pennsylvania