MGH Martinos Center for Biomedical Imaging 2016 | Page 16

focus on clinical applications

Improving Cancer Care With PET-MR
Researchers are translating the technique for clinical use
Incorporating positron emission tomography (PET)
into the clinical workflow can aid in diagnosing and
treating diseases by adding metabolic information to
the structural information provided by MRI.
This is especially true in oncology, where clinicians
want to interrogate in a single imaging session as many
aspects of a tumor as possible—“not just the size and
shape of a cancer,” said Onofrio Catalano, the Medical
Director of the MGH Martinos Center’s PET-MR program and an Assistant Professor of Radiology at Harvard Medical School, “but also its metabolism, its functional features, its genetics, and its response to therapy.”
To this end, Catalano has been exploring the potential
of the technique known as combined (18)-fluorodeoxyglucose (FDG) PET-MR. This multimodal approach
has a host of possible benefits for cancer patients. Chief
among these, of course, is the addition of metabolic information provided by PET. The combination of this The MGH Martinos Center’s Onofrio Catalano is seeking to advance
and MRI’s tissue characterization abilities is particularly clinical care in cancer patients using simultaneous PET-MR imaging.
Photo by Caroline Magnain.
useful in evaluating cancers involving, for example, the
central nervous system, bone marrow, pelvis and liver.
There are other advantages as well. Clinicians today can
acquire both metabolic and structural data, but typically only by performing separate PET-CT and MRI scans.
The use of whole-body integrated PET-MR would drastically reduce scan times, facilitating shorter exposures
to sedation and anesthesia when needed while also increasing the accuracy of the scans, the latter thanks to
the improved anatomic registration that comes with
simultaneous acquisition. In addition, it would offer
significantly reduced radiation dose compared to PETCT—at least 20-64 percent less, Catalano said.

cal role for the technique in the oncology population.
They showed excellent correlation between PET-MR
and PET-CT measurements performed in the same patients on the same day, if not also better staging accuracy achieved by PET-MR.

The researchers are now working to advance the technique still further, moving it ever closer to widespread
implementation in the clinic. With the Center’s Thomas
Witzel, Catalano is developing faster sequences for use
in PET-MR to reduce the total acquisition time. Also,
with the Center’s Ciprian Catana and his group, includCatalano and colleagues at the Martinos Center and ing instructor David Izquierdo-Garcia and postdocelsewhere described their preliminary experience with toral fellow Niccolo Fuin, he is developing other MR
simultaneous whole-body (18)-FDG PET-MR in a se- sequences uniquely applicable to PET-MR. They are
ries of papers published in major medical journals, in- planning to validate these soon, he said.
cluding Radiology, British Journal of Cancer, and World
Journal of Radiology. Their findings supported a clini-