The first combined MRI/PET machine is being tested on brain cancer patients.
New imaging technology shows promise in future cancer treatment
Many patients being treated for cancer are familiar with the seemingly endless exams and testing procedures to monitor their treatment progress. Now researchers at the Massachusetts General Hospital Cancer Center (Cancer Center) are working with a new technology that will soon save patients time and may often mean one less trip to the hospital.
A first ever combination Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET) prototype machine is being tested on brain cancer patients at the Cancer Center. It is the only place in the world that this machine is being used in clinical trials. Not only does it show its value with a convenience factor but researchers are optimistic that the combination MRI/PET imaging technology will soon translate into vast improvements in patient care.
MRI and PET scans are widely used separately by oncologists to monitor cancers and help determine if treatment protocols are shrinking cancer tumors. They are two very different and time-consuming tests that often cause patients additional anxiety and stress.
“This is an advance in technology that will make a big difference in people’s lives,” says A.Gregory Sorensen, MD, codirector of the Martinos Center for Biomedical Imaging at Massachusetts General Hospital. “MRI tests can determine the presence and structure of tumors. The PET scan shows what is happening within the cancer and the blood vessels surrounding it. We get much richer data from this imaging technology than we do from doing these two tests separately.
Most importantly, this will give doctors real-time information regarding which cancer therapies a patient might respond to quickly. This is critical because when you are treating cancer it is often a race against the clock. The combination MRI/PET technology prototype was developed by the Siemens Corporation after animal studies suggested this machine concept showed promise clinically. Sorensen and his team are working closely with neurologists from the Cancer Center who routinely treat patients with cancer of the brain. One important element they are gathering from these scan results in the patient is the complication of hypoxia, an oxygen deficiency. Brain tumors that become hypoxic are much more aggressive and dangerous.
“With the MRI/PET scan results we can determine the function and the role of blood vessels surrounding and within the tumor from the MRI component of the scan, and we can determine if a tumor is becoming hypoxic from the PET component,” explains Sorensen. “In addition, it now appears that with these advanced tools we may be able to very quickly determine if a particular drug therapy is working or not. If it is, then it can be continued; if the cancer is not responsive, though, it can then be stopped immediately, even after one day of treatment, and another treatment attempted.” Previously, oncologists often had to wait several weeks or months between scans.
The researchers here expect that the information they are gathering from these initial clinical trials will help with the MRI/PET machine design in the future and expand its use from brain imaging to whole body imaging. The National Cancer Institute’s Cancer Imaging Program (CIP) is helping to fund the clinical trials being conducted at Mass General with the single-scan MRI/PET technology.
“This is the imaging technology of the future for cancer patients,” says Sorensen. “We expect that over time we will see a very strong demand from oncologists worldwide to have and use this technology.”
For patients it will mean one less trip to the hospital and one less stressful scan to endure, and hopefully treatments that are more personalized to their particular needs.