Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study confirms colorectal cancer screening should start at age 50

04.09.2008
Colonoscopy best prevention method for colorectal cancer

Colorectal adenomas, the precursor polyps in virtually all colorectal cancers, occur infrequently in younger adults, but the rate sharply increases after age 50. Additionally, African Americans have a higher rate of proximal, or right-sided, polyps, and may have a worse prognosis for survival if the polyps become cancerous.

Therefore, the results of this study further emphasize the importance of colonoscopies, which view the entire colon, for the prevention of colorectal cancer beginning at age 50. The results of this study, which represents the largest investigation, by several-fold, of this kind, were published in Clinical Gastroenterology and Hepatology, the official journal of the American Gastroenterological Association (AGA) Institute.

"While colorectal polyps are rare in adults aged 30 to 50, our study reveals an increase in polyp prevalence with age and a dramatic increase in colorectal adenoma incidence occurring in adults over the age of 50," said Francis M. Giardiello, MD, of The John Hopkins University and lead author of the study. "Understanding the natural occurrence of colorectal polyps, especially in younger adults, is important to the development of colorectal cancer prevention strategies."

Findings

Researchers found the prevalence of colorectal polyps in younger adults increased from 1.72 percent to 3.59 percent from age 30 to 50. This rate sharply increased after age 50 with the prevalence of polyps ranging from 10.1 to 12.06 percent in the sixth and ninth decade, respectively. The study results quantified the number of adenomas typically found in people under the age of 50. It is important to note that those with two or more adenomas under 50 years of age represent unusual individuals who might merit closer colonoscopic surveillance for subsequent adenoma development.

In younger adults, adenomas were more prevalent in Caucasians compared to African Americans; however, in older adults, the reverse was true. Regardless of age, adenomas were more prevalent in men than women.

In the general population, left-sided adenomas are most common, but among older adults (age 50+), who have more adenomas, there is a relatively greater prevalence of right-sided adenomas. African Americans in both age groups had predominately right-sided polyps.

Implications for Colorectal Cancer Screening

The use of sigmoidoscopy as a screening test for colorectal cancer does not allow gastroenterologists to view the right-side of the colon to screen for polyps, only the rectum and the lower end of the colon. If a polyp or abnormality is found, patients may require a regular colonoscopy for further evaluation. Right-sided adenomas cannot be viewed using a sigmoidoscopy.

Colonoscopy, which provides the most comprehensive view of the colon, is the definitive test for colorectal cancer screening. Colonoscopies allow gastroenterologists to view the entire colon and rectum for polyps or cancer and during the same exam remove pre-cancerous polyps. It is the test most gastroenterologists recommend as the single best screening exam for colorectal cancer. It is the only method that combines both screening and prevention (by removal of pre-cancerous polyps).

Study Design

The study evaluated the large intestine of 3,558 autopsy subjects, aged 20-89, that had colorectal cancer undetected or unsuspected during life. Subjects were categorized by sex, race and age in 10 year groups. Location and number of colorectal adenomas detected was measured by using epidemiologic autopsy in individuals; results were standardized to the general population. The study's researchers evaluated the large intestine of 1,001 individuals undergoing necropsy between the ages of 20 and 49 for the presence of adenomas.

About Colorectal Cancer

While the incidence of colorectal cancer has declined in recent years, more than 153,000 people in the U.S. will be diagnosed with this cancer and more than 52,000 will die from the preventable disease. Americans have a 6 percent lifetime risk of colorectal cancer, which is the second leading cause of cancer death. When diagnosed early, colorectal cancer patients have a five-year survival rate of about 90 percent; however, fewer than 40 percent of patients present at an early stage.

To find more information about colorectal cancer and colonoscopies and locate a gastroenterologist in their area, patients can visit www.gastro.org/patient.

About the AGA Institute

The American Gastroenterological Association (AGA) is dedicated to the mission of advancing the science and practice of gastroenterology. Founded in 1897, the AGA is one of the oldest medical-specialty societies in the U.S. Comprised of two non-profit organizations—the AGA and the AGA Institute—our more than 16,000 members include physicians and scientists who research, diagnose and treat disorders of the gastrointestinal tract and liver. The AGA, a 501(c6) organization, administers all membership and public policy activities, while the AGA Institute, a 501(c3) organization, runs the organization's practice, research and educational programs. On a monthly basis, the AGA Institute publishes two highly respected journals, Gastroenterology and Clinical Gastroenterology and Hepatology. The organization's annual meeting is Digestive Disease Week®, which is held each May and is the largest international gathering of physicians, researchers and academics in the fields of gastroenterology, hepatology, endoscopy and gastrointestinal surgery.

About Clinical Gastroenterology and Hepatology

The mission of Clinical Gastroenterology and Hepatology is to provide readers with a broad spectrum of themes in clinical gastroenterology and hepatology. This monthly peer-reviewed journal includes original articles as well as scholarly reviews, with the goal that all articles published will be immediately relevant to the practice of gastroenterology and hepatology.

Aimee Frank | EurekAlert!
Further information:
http://www.gastro.org
http://www.cghjournal.org

More articles from Studies and Analyses:

nachricht Graphene gives a tremendous boost to future terahertz cameras
16.04.2019 | ICFO-The Institute of Photonic Sciences

nachricht Mount Kilimanjaro: Ecosystems in Global Change
28.03.2019 | Julius-Maximilians-Universität Würzburg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Explosion on Jupiter-sized star 10 times more powerful than ever seen on our sun

A stellar flare 10 times more powerful than anything seen on our sun has burst from an ultracool star almost the same size as Jupiter

  • Coolest and smallest star to produce a superflare found
  • Star is a tenth of the radius of our Sun
  • Researchers led by University of Warwick could only see...

Im Focus: Quantum simulation more stable than expected

A localization phenomenon boosts the accuracy of solving quantum many-body problems with quantum computers which are otherwise challenging for conventional computers. This brings such digital quantum simulation within reach on quantum devices available today.

Quantum computers promise to solve certain computational problems exponentially faster than any classical machine. “A particularly promising application is the...

Im Focus: Largest, fastest array of microscopic 'traffic cops' for optical communications

The technology could revolutionize how information travels through data centers and artificial intelligence networks

Engineers at the University of California, Berkeley have built a new photonic switch that can control the direction of light passing through optical fibers...

Im Focus: A long-distance relationship in femtoseconds

Physicists observe how electron-hole pairs drift apart at ultrafast speed, but still remain strongly bound.

Modern electronics relies on ultrafast charge motion on ever shorter length scales. Physicists from Regensburg and Gothenburg have now succeeded in resolving a...

Im Focus: Researchers 3D print metamaterials with novel optical properties

Engineers create novel optical devices, including a moth eye-inspired omnidirectional microwave antenna

A team of engineers at Tufts University has developed a series of 3D printed metamaterials with unique microwave or optical properties that go beyond what is...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

First dust conference in the Central Asian part of the earth’s dust belt

15.04.2019 | Event News

Fraunhofer FHR at the IEEE Radar Conference 2019 in Boston, USA

09.04.2019 | Event News

 
Latest News

New automated biological-sample analysis systems to accelerate disease detection

18.04.2019 | Life Sciences

Explosion on Jupiter-sized star 10 times more powerful than ever seen on our sun

18.04.2019 | Physics and Astronomy

New eDNA technology used to quickly assess coral reefs

18.04.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>