We tested the hypothesis that proton magnetic resonance spectroscopic imaging (1H-MRSI) can be used as a supportive diagnostic tool to differentiate clinically stable brain tumors from those progressing as a result of either low-to-high grade malignant transformation or of post-therapeutic recurrence. Twenty-seven patients with histologically verified cerebral gliomas were studied repeatedly with 1H-MRSI over a period of 3.5 years. At the time of each 1H-MRSI study, clinical examination, MRI, positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG), and biopsy findings (when available) were used to categorize each patient as being either «stable» or «progressive». Measures of the between-studies percent changes in the choline 1H-MRSI signal intensity, obtained without knowledge of the clinical categorization, segregated the groups with a high degree of statistical significance. All progressive cases showed a between-studies choline signal increase of more than 45%, while all stable cases showed an elevation of less than 35%, no change, or even a decreased signal. We conclude that increased choline coincides with malignant degeneration of cerebral gliomas, and therefore, may possibly be used as a supportive indicator of malignant degeneration of these neoplasms.
Perfusion, diffusion and spectroscopy values in newly diagnosed cerebral gliomas
