New Blood Test Finds Cancer Cells

A new cancer blood test may help doctors find cancers earlier
and monitor cancer treatment.

The new blood test uses microchip technology to sift blood to search for
circulating tumor cells (CTCs), which come from solid tumors and roam through
the blood.

The developers of the test call it a "new and effective tool"
that has "broad implications" for cancer research, detection,
diagnosis, and management.

"While much work remains to be done, this approach raises the
possibility of rapidly and noninvasively monitoring tumor response to
treatment, allowing changes if the treatment is not effective, and the
potential of early detection screening in people at increased risk for
cancer," Daniel Haber, MD, says in a news release.

Haber directs the Massachusetts General Hospital Cancer Center. He worked on
the study with researchers including Sunitha Nagrath, PhD, and Mehmet Toner,
PhD, of Massachusetts General Hospital.


New Cancer Blood Test

CTCs are hard to find because they're rare, accounting for one in a billion
in cancer patients' blood, according to the scientists who designed the CTC
blood test.

"We developed a counterintuitive approach, using a tiny chip with
critical geometrical features smaller than a human hair to process large
volumes of blood in a very gentle and uniform manner -- almost like putting a
'hose' through a microchip," Toner says in a news release.

The scientists tested the CTC blood test on 116 cancer patients, including
people with lung cancer , breast cancer , prostate cancer , pancreatic cancer , and colon cancer .

The test spotted CTCs in the blood samples from 99% of the cancer patients.
The test detected CTCs even when there were only 5 CTCs in a milliliter of a
patient's blood.

The test found no CTCs in blood samples from 20 healthy people.

In another experiment, the researchers used the blood test to monitor
changes in CTC levels in cancer patients undergoing treatment.

"The chip seems to be highly sensitive," says Jonathan Uhr, MD, in
an editorial published with the study in tomorrow's edition of

Uhr works at the University of Texas Southwestern Medical Center in

By Miranda Hitti
Reviewed by Louise Chang
©2005-2006 WebMD, Inc. All rights reserved