Screenings: Colonoscopy Suggestion May Be Made Too Often

By ERIC NAGOURNEY
Colonoscopies are a proven means of detecting small growths and removing them before they become deadly, but a new study suggests that many doctors are recommending them too often.
The study, in the December issue of The American Journal of Preventive Medicine, was led by Dr. Alex H. Krist of the Virginia Commonwealth University Medical Center in Richmond.
Researchers examined the records of 10 primary-care practices in Virginia and Maryland in 2006. They drew a random sample of 300 patients, ages 50 to 70, from each practice and looked at reports sent to the doctors.
The study found that about 60 percent of the time, the reports suggested that the patients return for a new colonoscopy sooner than the guidelines called for by the American Cancer Society and the American Gastroenterological Association.
In high-risk cases — patients who had a lot of polyps, large polyps of a family history of colon cancer — the doctors were more likely to follow the guidelines for that group.
Tests might be recommended sooner than called for by the guidelines, the researchers said, if, for example, an endoscopist did not get a clear view of the colon.

Number of Adenomas Strongest Predictor for Advanced Neoplasia

October 19, 2007 (Philadelphia) — The presence of 3 or more adenomas is the strongest predictor for identifying individuals with advanced neoplasias and high-recurrence risk status on follow-up colonoscopy, a study presented here has found.
Carol Burke, MD, director of the Center for Polyps and Cancer at the Cleveland Clinic in Ohio, described data from the study during a session at the American College of Gastroenterology 2007 Annual Scientific Meeting. The study aimed to determine which factors can predict recurrent advanced neoplasia or can be classified as a high recurrence risk at follow-up colonoscopy.
The study included 800 subjects, drawn from 3 postpolypectomy chemoprevention trials dating back to 1984, who had at least 1 baseline adenoma and who had undergone complete polypectomy. Subjects had to have a 3-year follow-up postpolypectomy colonoscopy, and individuals who had colorectal cancer on the baseline examination were excluded. Mean age at the time of randomization was 60 years, and the mean time of follow-up colonoscopy was 37 months.
Subjects were categorized as low risk or high risk for the recurrence of advanced neoplasia based on Multi-Society Task Force criteria, which recommend different surveillance intervals based on adenoma features: 5 to 10 years for individuals with low recurrence risk (<> 2 adenomas, ≥ 10 mm). Advanced neoplasia was defined as adenoma larger than 9 mm.
A multivariate regression analysis was used to obtain risk ratios (RRs) for the outcomes on the basis of baseline adenoma characteristics and the subjects' risk group.
The study found that high-risk status at baseline was significantly associated with recurrent advanced neoplasia (RR, 1.9; 95% confidence interval [CI], 1.2 - 3.0; P = .01) and high-risk status on follow-up colonoscopy (RR, 2.1; 95% CI, 1.5 - 3.1; P < .0001). Adenoma multiplicity was associated with both outcomes, but pathology was not associated with either outcome, and large size was only associated with advanced neoplasia.
"Individuals with advanced adenoma at baseline were twice as likely as individuals with a nonadvanced adenoma to have a follow-up advanced neoplasm," Dr. Burke told attendees. Sex, race, or family history of colorectal cancer did not predict an advanced neoplasm or a high-risk status, she added.
"The implication is that we all, when doing colonoscopies, should be diligent in efforts to detect synchronous neoplasia" to recommend the proper postpolypectomy interval, Dr. Burke concluded.
Commenting on the findings, Amy Foxx-Orenstein, MD, president of the American College of Gastroenterology and an associate professor of medicine at the Mayo Clinic in Rochester, Minnesota, said, "The interesting thing is that the number of polyps appears to be the issue. We need to have screening tools that allow us to identify those polyps maximally."
However, this raises a question about computed tomography (CT) colonography, said Dr. Foxx-Orenstein, who moderated the session. Although recent data have suggested that CT colonography is very good at identifying larger lesions, "the smaller lesions may be missed," she said. "And if it's the number of polyps that you're actually looking at, does that therefore raise an issue as to how valuable that tool might be or what we might be missing?"
Drs. Burke and Foxx-Orenstein have disclosed no relevant financial relationships.
American College of Gastroenterology 2007 Annual Scientific Meeting: Abstract 9. Presented October 15, 2007.

ACG: Colonoscopy's Benefits Extend to 80 and Beyond

PHILADELPHIA, Oct. 17 -- The benefits of screening colonoscopy extend to patients 80 and older, according to two studies reported here.Detection of asymptomatic early-stage colon cancer conferred a significant (P<0.005) survival advantage through age 85, Emily Singh, M.D., of the Scripps Clinic in La Jolla, Calif., said at the American College of Gastroenterology meeting.
In contrast, disease stage at diagnosis did not influence survival in symptomatic patients.
"The survival in asymptomatic patients results extend from ages 40 through 84 years," said Dr. Singh. "Recognizing that the average life expectancy at 80 years, without significant comorbidities, is nine years, we conclude that there is a role for screening colonoscopy in patients without significant comorbidities at least to age 85."
Roy Yen, M.D.University of BuffaloBuffalo, NY A second study provided additional support for screening colonoscopy in patients ages 80 and older. The study showed similar survival following screening colonoscopy for patients ages 70 through 79 and those ages 80 and older, said Roy Yen, M.D., of the University of Buffalo in New York.
Screening colonoscopy for older patients remains contentious, as no clear evidence or consensus exists to show that the benefits of screening end at a certain age, said Dr. Singh. Without adequate data, the controversy will likely intensify as the population ages. The population ages 65 and older is expected to exceed 72 million by 2030, more than double the number in 2000.
Dr. Singh and colleagues retrospectively analyzed data from a cancer registry to identify patients diagnosed with pathology-proven colorectal cancer from January 2000 through December 2005. The analysis identified 356 patients, 113 of them classified as asymptomatic and 242 or symptomatic.
The asymptomatic group comprised 81 patients with early-stage disease (0-IIB) and 32 with late-stage disease (III-IV). The symptomatic patients consisted of 130 with early disease and 113 with late-stage disease.
With a median follow-up of 2.5 years from diagnosis, detection of early-stage disease resulted in a significant survival advantage across all ages in the asymptomatic group. Men and women benefited, regardless of age.
Similar findings emerged from the Buffalo study, which was derived from data on 587 screening or surveillance colonoscopies. The study population included 58 patients who were 80 or older at the time of their colonoscopy procedures.
Colonoscopy detected significantly more adenomas in older patients (41.1% versus 26.0%, P=0.02) and more colon cancers (7.1% versus 2.1%, P=0.02). Older patients also had more proximal adenomas (28.6% versus 11.7%, P<0.01) and proximal colon cancer (5.4% versus 1.3%, P=0.03).
During 2.5-year follow-up after colonoscopy, 75.2% of the older patients were alive, which was not significantly different from the 83.2% survival observed in patients ages 70 to 79.
"These results suggest that patients 80 years and older may still benefit from screening colonoscopy," said Dr. Yen. "However, the findings need to be confirmed in additional studies."
Dr. Singh, Dr. Yen, and their coinvestigators declared no conflicts.Primary source: American College of GastroenterologySource reference: Yen RD et al. "Screening colonoscopy in patients older than 80 years." American College of Gastroenterology Annual Meeting and Postgraduate Course. Oct. 12-17, 2007. Philadelphia. Abstract 1000. Additional source: American College of GastroenterologySource reference: Singh EG et al. "Screening colonoscopy in the elderly. Is it worthwhile?" American College of Gastroenterology Annual Meeting and Postgraduate Course. Oct. 12-17, 2007. Philadelphia. Abstract 1001.