IntroductionIn conventional MR examination glioblastomas multiforme (GBM), metastases and primary CNS lymphomas (PCNSLs) may show very similar appearance. The aim of the study was to evaluate usefulness of multiparametric DSC perfusion and diffusion MR imaging in the preoperative differentiation of these tumors.Material and MethodsFifty three solitary enhancing tumors (20 GBMs, 20 metastases, 13 PCNSLs) were enrolled in the study. Parameters of cerebral blood volume (rCBV), peak height (rPH), percentage of signal recovery (rPSR) and apparent diffusion coefficient (ADC) were assessed from the tumor core and peritumoral non-enhancing T2-hyperintense zone.\u00a0Results Within the tumor core there were no differences in perfusion and diffusion parameters between GBMs and metastases. Compared to GBMs and metastases, PCNSLs showed significantly lower rCBV and rPH, ADC as well as higher rPSR values. Max rCBV with a cut-off value of 2.18 showed the highest accurracy of 0.98 in differentating PCNSLs from other tumors. To distinguish GBMs from metastases analysis of the peritumoral zone was performed showing significantly higher rCBV, rPH and lower ADC values in GBMs with the highest accuracy of 0.94 found for max rCBV at a cut-off value of 0.98.Conclusions Max rCBV seems to be the most important parameter to differentiate GBMs, metastases and PSCNSLs. Analysis of max rCBV within a tumor core enables to distinguish hypoperfused (PCNSLs) from hyperperfused (GBMs and metastases) tumors while evaluation of max rCBV within the peritumoral zone is helpful to distinguish GBMs showing peritumoral infiltration from metastases surrounded by pure edema.