HIGH AMINO-ACID-UPTAKE IN A LOW-GRADE DESMOPLASTIC INFANTILE GANGLIOGLIOMA IN A 14-YEAR-OLD PATIENT

Amino acid uptake is higher in high-grade than in low-grade gliomas; t his is the rationale for using radioactively labelled amino acids for the non-invasive grading of brain neoplasms. We present a 14-year-old boy with a low-grade desmoplastic infantile ganglioglioma (DIG) that e xhibited marked contrast enhancement on magnetic resonance imaging (MR I), but no signs of infiltration and only minimal surrounding edema. I n this benign neoplasm the relative uptake of the radioactively labell ed amino acid I-123-alpha-methyl tyrosine (IMT), determined using sing le-photon emission computed tomography (SPECT), was 3.24; it was consi derably higher than that of eleven other pretherapeutic low-grade glio mas where it ranged from 1.06 to 1.94 and also markedly above the aver age value of 2.37 found in 20 high-grade gliomas. This case report ill ustrates that results from emission tomography with radioactively labe lled amino acids must be interpreted with caution, particularly when r are tumor entities are considered in view of uncommon clinical or radi ological findings.