The efficacy of dual time point F-18 FDG PET imaging for grading of brain tumors.

PURPOSE: Several studies have explored the usefulness of dual time point F-18 FDG positron emission tomography imaging (DTPI) in improving detection of brain metastases and tumors outside the brain, distinguishing malignant from benign. In the same manner, DTPI may show better performance to grade of brain tumors.
METHODS: Twenty-two lesions of 18 consecutive patients with primary or metastatic brain tumor were included prospectively. DTPI was performed and analyzed using maximum standardized uptake values (SUVmax), mean standardized uptake values within isocontour at 70% of maximum pixel values (SUViso), and retention index (RI) for each lesion.
RESULTS: SUVmax and SUViso of the delayed image were more efficient than those of early images to classify lesions by the grade of tumors. The RI of SUVmax and SUViso were not significant to classify lesions.
CONCLUSION: DTPI may be a better imaging method to grade the brain tumor than early imaging only.