New MRI Technique Helps Diagnose Gliomas

January 27, 2012

A new magnetic resonance spectroscopy technique provides a definitive diagnosis of brain cancer based on imaging of a protein associated with a mutated gene.

A new magnetic resonance spectroscopy (MRS) technique provides a definitive diagnosis of brain cancer based on imaging of a protein associated with a mutated gene found in 80 percent of low- and intermediate-grade gliomas, according to a new study published January 26 in Nature Medicine.

Researchers at the University of Texas Southwestern Medical Center say theirs is the first clinical application of a new imaging technique to diagnose brain tumors. The test could preclude the need for surgery in patients whose tumors are located in areas of the brain too dangerous to biopsy, they say.

“To our knowledge, this is the only direct metabolic consequence of a genetic mutation in a cancer cell that can be identified through noninvasive imaging,” said Elizabeth Maher, MD, associate professor of internal medicine and neurology at UT Southwestern and senior author of the study “This is a major breakthrough for brain tumor patients.”

The team developed the test by modifying the settings of an MRI scanner to track levels of protein 2-hydroxyglutarate (2HG) in brain tumors. The protein’s accumulation is associated with mutations in isocitrate dehydrogenases 1 and 2 (IDH1 and IDH2) in most grade 2 and grade 3 gliomas in adults.

The data acquisition and analysis was developed by lead author and UT Southwestern radiologist Changho Choi, MD.

To confirm the MRI test, the team analyzed biopsy samples from 30 glioma patients enrolled in the a clinical trial. Half had the mutation and high levels of the protein. MRS imaging of these patients done before surgery predicted which patients had the mutation with 100 percent accuracy.