Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Improved DNA stool test could detect digestive cancers in multiple organs

Mayo Clinic researchers have demonstrated that a noninvasive screening test can detect not only colorectal cancer but also the common cancers above the colon -- including pancreas, stomach, biliary and esophageal cancers. This is one of more than 100 Mayo Clinic studies being presented at Digestive Disease Week 2009 in Chicago, May 30 – June 4.

Gastrointestinal (GI) cancers account for approximately one in four cancer deaths. While high cure rates can be achieved with early-stage detection for each type, only colorectal cancer is currently screened at the population level.

Most people associate colorectal cancer screening with invasive colonoscopy, but previous Mayo Clinic research has shown that stool DNA testing can identify both early-stage colorectal cancer and precancerous polyps. Researchers are now studying the use of noninvasive stool DNA testing to detect lesions and cancer throughout the GI tract.

"Patients are often worried about invasive tests like colonoscopies, and yet these tests have been the key to early cancer detection and prevention," says David Ahlquist, M.D., Mayo Clinic gastroenterologist and lead researcher on the study. "Our research team continues to look for more patient-friendly tests with expanded value, and this new study reveals an opportunity for multi-organ digestive cancer screening with a single noninvasive test."

The researchers studied 70 patients with cancers throughout the digestive tract. Besides colon cancer, the study looked at throat, esophagus, stomach, pancreatic, bile duct, gallbladder and small bowel cancers to determine if gene mutations could be detected in stool samples. Using a stool test approach developed at Mayo Clinic, researchers targeted DNA from cells that are shed continuously from the surface of these cancers. Also studied were 70 healthy patients. Stool tests were performed on cancer patients and healthy controls by technicians unaware of sample source. The stool DNA test was positive in nearly 70 percent of digestive cancers but remained negative for all healthy controls, thus demonstrating the approach's feasibility.

Stool DNA testing detected cancers at each organ site, including 65 percent of esophageal cancers, 62 percent of pancreatic cancers, and 75 percent of bile duct and gallbladder cancers. In this series, 100 percent of both stomach and colorectal cancers were detected. Importantly, stool test results did not differ by cancer stage; early-stage cancers were just as likely to be detected as late-stage cancers.

"It's very exciting to see this level of sensitivity for digestive cancer detection in our first look at this test application," says Dr. Ahlquist, "Historically, we've approached cancer screening one organ at a time. Stool DNA testing could shift the strategy of cancer screening to multi-organ, whole-patient testing and could also open the door to early detection of cancers above the colon which are currently not screened. The potential impact of this evolution could be enormous."

In October 2008, this Mayo Clinic research team published results of a multicenter study using first-generation stool DNA testing. In the seven-year, multicenter study (Ann Intern Med 2008;149:441-50), researchers found that the first-generation stool DNA tests were better than fecal blood tests for detecting cancer and precancerous polyps of the colon. In January 2009 (Gastroenterology 2009;136:459-70), Mayo researchers published some technical improvements that nearly doubled the sensitivity of stool DNA testing for detecting premalignant polyps and increased cancer detection to about 90 percent, which is the approximate rate of detection observed for CT colonography.

Researchers hope that the next generation tests will have significant improvements in accuracy, processing speed, ease of patient use and affordability. "We anticipate that next generation tests will also be able to predict the tumor site, which will help physicians direct diagnostic studies and minimize unnecessary procedures," says Dr. Ahlquist.

Dr. Ahlquist and Mayo Clinic have a financial interest related to technology studied in this research.

Other researchers from Mayo Clinic include: Hongzhi Zou, M.D., Ph.D; Jonathan Harrington; William Taylor; Mary Devens; Xiaoming Cao, M.D.; Russell Heigh, M.D.; Yvonne Romero, M.D.; Suresh Chari, M.D.; Gloria Petersen, Ph.D.; Lewis Roberts, M.B.Ch.B., Ph.D.; Jan Kasperbauer, M.D.; Julie Simonson; David I. Smith, Ph.D.; and Thomas Smyrk, M.D.

Mayo Clinic's Division of Gastroenterology and Hepatology has been ranked #1 in the U.S. News & World Report Honor Roll of Top Hospitals since the rankings began 19 years ago.

About Mayo Clinic

Mayo Clinic is the first and largest integrated, not-for-profit group practice in the world. Doctors from every medical specialty work together to care for patients, joined by common systems and a philosophy of "the needs of the patient come first." More than 3,300 physicians, scientists and researchers and 46,000 allied health staff work at Mayo Clinic, which has sites in Rochester, Minn., Jacksonville, Fla., and Scottsdale/Phoenix, Ariz. Collectively, the three locations treat more than half a million people each year. To obtain the latest news releases from Mayo Clinic, go to For information about research and education, visit ( is available as a resource for your health stories.

Amy Tieder | EurekAlert!
Further information:

More articles from Health and Medicine:

nachricht Advanced analysis of brain structure shape may track progression to Alzheimer's disease
26.10.2016 | Massachusetts General Hospital

nachricht Indian roadside refuse fires produce toxic rainbow
26.10.2016 | Duke University

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Novel light sources made of 2D materials

Physicists from the University of Würzburg have designed a light source that emits photon pairs. Two-photon sources are particularly well suited for tap-proof data encryption. The experiment's key ingredients: a semiconductor crystal and some sticky tape.

So-called monolayers are at the heart of the research activities. These "super materials" (as the prestigious science magazine "Nature" puts it) have been...

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Prototype device for measuring graphene-based electromagnetic radiation created

28.10.2016 | Power and Electrical Engineering

Gamma ray camera offers new view on ultra-high energy electrons in plasma

28.10.2016 | Physics and Astronomy

When fat cells change their colour

28.10.2016 | Life Sciences

More VideoLinks >>>