Featured Research

from universities, journals, and other organizations

First Colonoscopy With Removal Of Polyps Linked To Reduction In Colon Cancer Death

Date:
October 29, 2007
Source:
American College of Gastroenterology
Summary:
Using a model from the National Polyp Study data, researchers found a dramatic reduction in expected colorectal cancer deaths with screening colonoscopy that cleared the colon of precancerous polyps -- whether or not there were follow-up exams -- suggesting the initial screening with "polypectomy" may account for mortality reduction.

Using a model to predict reductions in death from colorectal cancer, epidemiologists and clinical researchers from Memorial Sloan-Kettering looked at the relative effect of an initial screening colonoscopy which clears pre-cancerous polyps from the colon versus surveillance follow-up colonoscopy. Ann G. Zauber, Ph.D., Sidney J. Winawer, M.D., MACG and colleagues presented their findings at the Annual Scientific Meeting of the American College of Gastroenterology.

"The model demonstrated a dramatic reduction in expected colorectal cancer mortality with initial polypectomy with or without surveillance, and suggests that the initial polypectomy accounts for the major component of the mortality reduction," explained Dr. Zauber.

Using a "MISCAN" model, researchers used National Polyp Study data to predict colorectal cancer mortality among three groups of patients: those with no initial removal of polyps or follow-up surveillance by colonoscopy, compared to patients with only initial polypectomy, and those with both polypectomy and follow-up surveillance. The model predicted mortality of up to thirty years after the initial colorectal exam and removal of pre-cancerous polyps.

According to Dr. Zauber, the major effect on colorectal cancer mortality reduction produced by the initial polypectomy rather than the surveillance colonoscopies is consistent with the low incidence of advanced adenomas observed during National Polyp Study (NPS) follow-up (i.e., pre-cancerous growths in the colon larger than 1 cm, polyps with a villous component, high grade dysplasia or invasive colorectal cancer.)

Dr. Zauber and her colleagues suggest that these findings may support the recommendation to lengthen the interval to six or more years for follow-up surveillance for patients who have polyps removed. Current recommendations by the American College of Gastroenterology call for surveillance colonoscopy in three to five years for follow-up of patients with prior colorectal cancer, prior adenomas or disease with causes increased risk of colorectal cancer.

An editorial by colorectal cancer expert T.R. Levin, M.D, FACG in the August issue of the American Journal of Gastroenterology offers an overview of post-polypectomy surveillance. According to Dr. Levin: "Postpolypectomy and postcancer resection surveillance are among the most common indications for colonoscopy in clinical practice. Together, they account for more than one in five colonoscopies in the Clinical Outcomes Research Initiative (CORI) database. Survey results have also demonstrated that postpolypectomy surveillance for small adenomas and hyperplastic polyps is often recommended by specialists and primary care physicians more frequently than guideline recommendations."* Dr. Levin commented on a study in the same issue of the American Journal of Gastroenterology by Brenner et al. from Germany which Levin believes presents additional evidence to justify extending colonoscopy intervals following polypectomy to five years. According to Levin, performing excessive surveillance colonoscopy is a problem for two reasons. It drains resources better used for initial colorectal cancer screening and diagnosis, and patients are exposed to potential risks associated with each colonoscopy with little benefit.

According to ACG President Dr. David A. Johnson, "there is growing evidence to support the extension of surveillance to longer intervals, all subject to optimal clearing of the colon of precancerous polyps -- which is contingent on adequate resection at the time of polypectomy and adequate visualization of the colon, which depends on adequate bowel preparation, as well as efforts by the endoscopist during the exam. Although given the constraints of a modeling study such as this one from Sloan-Kettering, there need to be prospective trials to support and validate longer colorectal cancer surveillance intervals before changing the current recommendations."

* Levin TR, "Dealing With Uncertainty: Surveillance Colonoscopy After Polypectomy," Am J Gastroenterol 2007;102:1745--1747


Story Source:

The above story is based on materials provided by American College of Gastroenterology. Note: Materials may be edited for content and length.


Cite This Page:

American College of Gastroenterology. "First Colonoscopy With Removal Of Polyps Linked To Reduction In Colon Cancer Death." ScienceDaily. ScienceDaily, 29 October 2007. <www.sciencedaily.com/releases/2007/10/071015081447.htm>.
American College of Gastroenterology. (2007, October 29). First Colonoscopy With Removal Of Polyps Linked To Reduction In Colon Cancer Death. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2007/10/071015081447.htm
American College of Gastroenterology. "First Colonoscopy With Removal Of Polyps Linked To Reduction In Colon Cancer Death." ScienceDaily. www.sciencedaily.com/releases/2007/10/071015081447.htm (accessed July 24, 2014).

Share This




More Health & Medicine News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Idaho Boy Helps Brother With Disabilities Complete Triathlon

Idaho Boy Helps Brother With Disabilities Complete Triathlon

Newsy (July 23, 2014) An 8-year-old boy helped his younger brother, who has a rare genetic condition that's confined him to a wheelchair, finish a triathlon. Video provided by Newsy
Powered by NewsLook.com
Thousands Who Can't Afford Medical Care Flock to Free US Clinic

Thousands Who Can't Afford Medical Care Flock to Free US Clinic

AFP (July 23, 2014) America may be the world’s richest country, but in terms of healthcare, the World Health Organisation ranks it 37th. Thousands turned out for a free clinic run by "Remote Area Medical" with a visit from the Governor of Virginia. Duration: 2:40 Video provided by AFP
Powered by NewsLook.com
Stone Fruit Listeria Scare Causes Sweeping Recall

Stone Fruit Listeria Scare Causes Sweeping Recall

Newsy (July 22, 2014) The Wawona Packing Company has issued a voluntary recall on the stone fruit it distributes due to a possible Listeria outbreak. Video provided by Newsy
Powered by NewsLook.com
Huge Schizophrenia Study Finds Dozens Of New Genetic Causes

Huge Schizophrenia Study Finds Dozens Of New Genetic Causes

Newsy (July 22, 2014) The 83 new genetic markers could open dozens of new avenues for schizophrenia treatment research. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins