SNMMI: Amino acid PET helps shed light on pediatric glioma

Use of O-(2-[18F]-fluoroethyl)-L-tyrosine (F-18 FET), an amino acid PET agent, was shown to be highly accurate in identifying brain lesions in children suspected of glioma cerebral cancer, according to a study presented at the Society of Nuclear Medicine and Molecular Imaging’s 2013 annual meeting in Vancouver.

“Our findings suggest that in children and young adults FET PET can add relevant additional clinical information for treatment planning and monitoring when MRI is equivocal,” wrote Veronika Dunkl, MD, of the Institute of Neuroscience and Medicine, Jülich Research Centre, in Jülich, Germany, and colleagues in the study abstract.

Amino acid PET imaging has been shown to improve detection of brain cancers over glucose imaging, which produces images of the brain with less definition due to the high cellular metabolism of brain cells.

The retrospective study focused on the use of F-18 FET imaging in a group of 22 patients between three and 17 years of age. All patients were selected due to MRI results suggesting neoplastic tissue/glioma or to rule out tumor progression or residual tumors. A total of 32 PET scans were acquired.

Results showed that in the patients with suspected neoplastic tissue, F-18 FET was able to correctly identify which lesions were tumors and which were non-neoplastic with 87 percent accuracy, according to the researchers.

Dunkl and colleagues added that repeated PET imaging resulted in 94 percent accuracy for ruling out tumor progression or residual tumor in a subgroup of seven patients.

F-18 PET is an attractive imaging option because unlike other amino acid PET agents, it has a long half-life allowing it to be centrally produced at a radiopharmacy rather than an on-site cyclotron, according to the researchers.