Proton magnetic resonance spectroscopy in differentiating glioblastomas from primary cerebral lymphomas and brain metastases.

Overview

OBJECTIVE: To differentiate glioblastomas, primary cerebral lymphomas (PCLs), and brain metastases using multivoxel proton magnetic resonance (MR) spectroscopic imaging. METHODS: A total of 56 patients with brain neoplasms underwent MR imaging and proton MR spectroscopic imaging. The data were analyzed from contrast-enhancing and peritumoral regions (PTR). N-acetylaspartate/creatine (Cr), choline (Cho)/Cr, glutamate+glutamine/Cr, myo-inositol/Cr, and lipids+lactate/Cr ratios were computed, and pairwise comparisons between neoplasms were made using Mann-Whitney U tests. RESULTS: The PTR demonstrated most significant differences in metabolite ratios. The Cho/Cr ratio in glioblastomas (0.46 [0.01]) was significantly higher than that in metastases (0.38 [0.02], P = 0.01). Significantly elevated Cho/Cr levels were also noted in PCLs (0.48 [0.03]) compared with those in metastases (P = 0.04). In addition, PCLs also demonstrated significantly higher lipids+lactate/Cr levels (11.83 [2.59]) compared with glioblastomas (4.50 [0.59], P = 0.003) and metastases (2.79 [0.33], P = 0.001). CONCLUSIONS: Proton MR spectroscopic imaging from PTR may assist in the differentiation of glioblastomas, metastases, and PCLs.