Diffusion MRI predicts benefits of therapy

Using diffusion MRI, researchers at the University of Michigan Comprehensive Cancer Center developed a functional diffusion map that helps determine whether tumor therapy is working or not.

Thirty-four patients with late-stage diffuse high-grade gliomas underwent diffusion MRI before beginning chemotherapy, radiation therapy, or a combination. Three weeks later, the patients underwent another diffusion MRI. Ten weeks after that, the patients received a standard MRI (Proc Natl Acad Sci USA 2005; Oct. 31: early online edition).

At three weeks into treatment, and more than two months before the final MRI scan, researchers could identify which patients would have a response to therapy over those with progressive disease. This corresponded to patients' survival, with those classified as having progressive disease living an average 8.2 months. Patients predicted to respond to treatment lived an average 18.2 months.

The researchers believe the test may be useful for other types of cancer, including breast, head and neck, rectal, prostate, and liver. The functional diffusion map is not yet available for routine clinical use.