Dynamic Susceptibility Contrast-Enhanced Perfusion and Conventional MR Imaging Findings for Adult Patients with Cerebral Primitive Neuroectodermal Tumors

tumors (PNETs) from other tumors is important for presurgical staging, intraoperative man-agement, and postoperative treatment. Dynamic, susceptibility-weighted, contrast-enhanced MR imaging can provide in vivo assessment of the microvasculature in intracranial mass lesions. The purpose of this study was to determine the perfusion characteristics of adult cerebral PNETs and to compare those values with low and high grade gliomas. METHODS: Conventional MR images of 12 adult patients with pathologically proved cere-bral PNETs were analyzed and provided a preoperative diagnosis. Relative cerebral blood volume (rCBV) measurements and estimates of the vascular permeability transfer constant, Ktrans, derived by a pharmacokinetic modeling algorithm, were also obtained. These results were compared with rCBV and Ktrans values obtained in a group of low grade gliomas (n 30) and a group of high grade gliomas (n 55) by using a Student t test. RESULTS: On conventional MR images, PNETs were generally well-defined contrast-enhanc-ing masses with solid and cystic components, little or no surrounding edema, and occasional regions of susceptibility. The rCBV of cerebral PNETs was 4.76 1.99 SD, and the Ktrans was 0.0033 0.0035. A comparative group of patients with low grade gliomas (n 30) ha