Blasel S, et al. - This study was performed to examine the prognostic value of MR perfusion in primary CNS lymphomas (PCNSL). Predictive factor for overall survival (OS) and progression-free survival (PFS) of PCNSL was patient age only, but not MR perfusion parameters and features. Most PCNSL showed the typical shoulder-like increase of the time–signal intensity curve (“TSIC-shoulder”), moderate size, peritumoral edema and regional cerebral blood volume (rCBV) increase. However, larger, solitary PCNSL additionally had a rCBV-sun pattern and more edema, could be because of a centrifugal vessel proliferation, while smaller, multifocal PCNSL contain apparently more concentrated and less permeable blood vessels represented by higher rCBV, no TSIC-shoulder, and less edema.