New noninvasive technique allows for early detection of chemotherapy treatment response

Scientists at the Arizona Cancer Center have developed an approach that will allow them to detect if cancer patients are responding within days after they start a new chemotherapy regimen. In addition to early detection of treatment response, the new technique is noninvasive, requiring no surgery or blood test.

The research team has published its findings in the November/December 2004 issue of the journal Neoplasia.

The technique is called diffusion magnetic resonance imaging (MRI), which allows investigators to see the rate at which water moves in tissues. Although this technique commonly is used in assessment of stroke in the brain, this group is one of a few in the world using it to measure cancer -- and is the only group using diffusion MRI to measure metastatic disease, where most new drugs are tried.

The group found that the rate of water movement was higher in cancers that responded to treatment, whereas there was no change in patients who did not respond. These changes could be seen as soon as four days after the beginning of therapy.

"Early detection of a response can enhance patient care by allowing oncologists to make more informed decisions on therapy choices," explains Dr. Alison Stopeck, an oncologist at the Arizona Cancer Center.

"Increased water mobility in responding tumors makes absolute sense," says Dr. Robert Gillies. "Both modeling and data tell us that water mobility should increase as cells respond to therapy. This measurement will have an important impact on early clinical trials for drug development."

The research was performed on MRI scanners at the University of Arizona Health Sciences Center. Two new scanners have been installed as a partnership between University Medical Center and the University of Arizona.

"The availability of dedicated research time on these new MRI scanners is vital to carrying out this work and will allow us to continue and improve this important research," Dr. Trouard says.