New Imaging Analysis Predicts Brain Tumor Survival

U-M researchers develop 'parametric response map' to analyze changes in a
tumor's blood flow, volume

ANN ARBOR, Mich., April 20 /PRNewswire-USNewswire/ -- As early as one week
after beginning treatment for brain tumors, a new imaging analysis method was
able to predict which patients would live longer, researchers from the
University of Michigan Comprehensive Cancer Center have found.

The method uses a standard magnetic resonance imaging, or MRI, protocol to
monitor changes over time in tumor blood volume within individual voxels of
the image, rather than a composite view of average change within the tumor.
This parametric response map allowed researchers to see specific areas in
which tumor blood volume increased or decreased, that may have canceled each
other out when looking at the changes as an average.

Results of the study appear in the advance online edition of Nature Medicine.

"What we have potentially is a generalized analytical approach that we can use
to quantify treatment intervention in patients," says study author Brian Ross,
Ph.D., professor of radiology and biological chemistry at the U-M Medical
School and co-director of the Molecular Imaging Program at the U-M
Comprehensive Cancer Center.

The researchers looked at 44 people with high-grade glioma, a type of brain
tumor, who were treated with chemotherapy and radiation. Each participant
underwent MRIs before treatment, and one week and three weeks after starting
treatment. The researchers then looked at the relative cerebral blood volume
and the relative cerebral blood flow of the tumor to analyze voxel-wise
changes among the serial scans.

Looking at standard comparisons using averages, the scans indicated no change
one week and three weeks into treatment. But, using the parametric response
map approach, the researchers were able to show changes in the tumor's blood
volume and blood flow after one week that corresponded to the patient's
overall survival.

"We're seeing treatment response earlier into the treatment, and responses
that couldn't be detected at all looking at average changes. We could detect
this after just one week, which is amazing for brain tumors," says study
author Craig Galban, Ph.D., assistant professor of radiology at the U-M
Medical School.

High grade gliomas have a high mortality rate, with people surviving only an
average of 12 months after diagnosis. Typically, patients receive six to seven
weeks of treatment, followed by a traditional MRI scan six weeks after
completing therapy to determine if the tumor shrank. If the cancer did not
respond to the treatment, a new approach may be tried.

The researchers believe this approach might also be useful with other imaging
techniques such as PET and CT scans.

Brain cancer statistics: 21,810 Americans will be diagnosed with brain cancer
this year and 13,070 will die from the disease, according to the American
Cancer Society

Additional authors:Thomas Chenevert, Ph.D.; Charles Meyer, Ph.D.; Christina
Tsien, M.D.; Theodore Lawrence, M.D., Ph.D.; Daniel Hamstra, M.D., Ph.D.;
Larry Junck, M.D.; Pia Sundgren, M.D., Ph.D.; Timothy D. Johnson, Ph.D.; David
Ross; and Alnawaz Rehemtulla, Ph.D.

Funding: National Institutes of Health

Disclosure: The University of Michigan has filed a patent application on this
technology.

Reference: Nature Medicine, doi: 10.1038/nm.1919

Resources:
U-M Cancer AnswerLine, 800-865-1125
U-M Comprehensive Cancer Center, www.mcancer.org

SOURCE University of Michigan Comprehensive Cancer Center

Nicole Fawcett, nfawcett@umich.edu, or Anne Rueter, arueter@umich.edu, both of
the University of Michigan Comprehensive Cancer Center, +1-734-764-2220