Push for less costly, invasive colonscopy alternatives
A colonoscopy, a dreaded medical procedure recommended for people 50 and older, is the best, one-shot way to screen and detect colon cancer for now, most health professionals agree.
But an increasing number of experts are beginning to voice support for alternative methods they say could be used more widely to prevent colorectal cancer, which occurs in the colon or rectum. The disease is the third most common cancer diagnosis for men and women and the second leading cause of cancer deaths in men and women combined.
The colonoscopy is the most commonly used colon cancer screening procedure in the country. It allows doctors to examine the entire colon and remove abnormal tissue growths called polpys that can turn into cancer.
A study published in the New England Journal of Medicine last month found that the removal of polyps by colonoscopy appears to cut the death rate from colorectal cancer in half.
But some professionals argue colonoscopy has been promoted as the “gold standard” to the point that other less invasive, lower cost options are routinely overlooked.
“I am not against colonoscopy. I'm against it being called the best test,” said Dr. James Allison, professor emeritus of medicine at UCSF and an adjunct investigator at the Kaiser Division of Research. He argued the New England Journal report showing that the colonoscopy is better than other available and recommended screening tests was not a randomized, controlled study.
Despite public urging by health officials, about a third of Americans ages 50 to 75 have never undergone any form of screening for the disease, which claims more than 50,000 lives a year. Studies have shown that people without insurance are more than 60 percent less likely to be screened than those who have health coverage.
But for the insured and uninsured alike, the colonoscopy is unpopular.
Allison, a gastroenterologist, contends more people might get screened if alternatives were encouraged.
He promotes increased use of the newest most sensitive form of stool sampling, a test called the fecal immunochemical test, or FIT.
A New England Journal report last month showed the FIT test had promise, but may miss some opportunities to detect polyps as compared with colonoscopy. Clinical trials are in progress to determine the effectiveness the FIT.
The San Francisco Department of Public Health in recent months adopted a yearly FIT-based screening program for its clinic patients, Allison said. Patients who have a positive FIT are referred to San Francisco General Hospital for colonoscopy.
Part of why patients tend not to follow through with screenings is that all the options have some unpleasantness. And having choices can create confusion.
Colonoscopy is the most invasive procedure and typically involves sedation. Patients who undergo a sigmoidoscopy, which examines only part of the colon, need less sedation, if any. It's less intrusive but raises concerns among patients that the procedure may miss potential disease. Some studies suggest more people participate in the FIT screening because it's the least invasive.
Many patients, given the options, often question why they shouldn't just go through a colonoscopy, considering they would have to do so anyway if the other tests indicate a possible problem.
Dr. Uri Ladabaum, director of the gastrointestinal cancer preventive program at Stanford University School of Medicine, said the evidence to date indicates that high-quality colonoscopy appears preferable to sigmoidoscopy. But the results of studies on frequent, consistent, highly sensitive fecal testing programs could show it performs well even against colonoscopy. That may lead to more people being screened.
“Getting some form of screening is better than none,” he said.