Medium-Sized Polyps More Dangerous than Thought

Even if they aren´t large, polyps can
be dangerous; © NCI Visuals Online

"An emerging issue in colorectal cancer screening is the management of medium-sized polyps, since many new technologies under development can only observe the lining of the colon, and do not offer the ability to remove polyps," said Robert Schoen, M.D., M.P.H, lead author of the study and professor of medicine and epidemiology, University of Pittsburgh School of Medicine.

"With these new methods, colonoscopy and polyp removal are required as second procedures, but because of issues of expense and risk, determining a specific threshold for subsequent procedures becomes an important issue. One area of uncertainty concerns medium-sized polyps."

In the study with 10,850 men and women, polyps 0.6 - 0.9 cm were found in 2,183 men and 1,426 women through flexible sigmoidoscopy, in which a scope is used to examine the inside of the large intestine from the rectum through the descending colon.

When the men and women in the study underwent diagnostic colonoscopy within a year, 14.5 percent of the women and 15.9 percent of the men were diagnosed with advanced adenomas (pre-cancerous polyps or growths in the lining of the large intestine that are at higher risk for developing into cancer), and 0.6 percent of the women and 0.7 percent of the men were diagnosed with cancer.

In some cases, the medium-sized polyps were considered large when removed and assessed at colonoscopy. In other cases, the small polyps had important, adverse pathologic characteristics once removed and studied under the microscope.

"The implication of our study is that where we draw the line when assessing and evaluating polyp size and referral to colonoscopy has to be carefully considered," said Dr. Schoen. "These results offer a cautionary note to waiting and watching."; Source: University of Pittsburgh Medical Center