Blood Tests May Detect Colon Cancer

Two new blood tests may help to make the
diagnosis of colon and other gastrointestinal cancers simpler, cheaper, and
less unpleasant.

The tests, developed by Belgian and German scientists, look for genetic
fingerprints of tumor growth in the blood. One test may also help to predict
whether cancer is likely to spread.

The tests were described here at a joint meeting of the European Cancer
Organization (ECCO) and the European Society for Medical Oncology.

ECCO President Alexander Eggermont, MD, head of surgical oncology at the
Erasmus University Medical Center in the Netherlands, tells WebMD that the
tests may help fill a need for more convenient cancer screening. He was not
involved with the work.

One in 17 people will develop colorectal cancer in his or her lifetime. It's
the second leading cancer killer in the U.S. and Europe.

The risk of dying is reduced substantially if the disease is caught early,
when it is most treatable. But many people shun current tests such as
colonoscopy and stool sample analysis, calling them invasive or just plain
nasty, says Joost Louwagie, PhD, of OncoMethylome Sciences in Liege, Belgium,
which is developing one of the tests.

Louwagie and colleagues collected blood samples from 193 patients undergoing
surgery for colorectal cancer and 688 people who were undergoing
colonoscopies.

They looked for two genes, SYNE1 and FOXE1, which have been linked to tumor
growth.

"We found a high frequency of these genes in colorectal patients. The same
genes occurred infrequently in noncancerous patients," Louwagie tells
WebMD.

Overall, the test correctly identified 50% to 60% of cancers, he says. And
it correctly identified more than 90% of people with no cancer.

In people with early-stage colon cancer , the test performed even better,
Louwagie says.

"Once validated, the new methylation test could be used as a noninvasive
screening option for patients who decline or do not have access to colonoscopy
or do not wish to undertake the fecal occult blood test."

"The blood sample can be taken by nurses or primary care doctors without the
need for special equipment or training, leading to higher rates of patient
compliance," he says.

The company is talking with several larger companies about licensing rights
to the test.

The second test, developed by Ulrike Stein, PhD, of the ECRC Charite
University of Medicine in Berlin, and colleagues, looks for colon, rectal, and
gastric cancers.

The test homes in on a genetic fingerprint, S100A4, that has been linked to
the development and spread of tumors.

The researchers studied daily blood samples from 185 people with colon
cancer, 190 people with rectal cancer , 91 gastric cancer patients, and 51
tumor-free volunteers.

"We found that S100A4 was present at significantly higher levels in the
group of cancer patients, no matter whether they had colorectal or gastric
cancer, than in the tumor-free control group," says Stein.

There were even higher levels in patients who cancer had spread, she
says.

By Charlene Laino
Reviewed by Louise Chang
©2005-2008 WebMD, LLC. All rights reserved