Specific Features of Primary Central Nervous System Lymphoma in Comparison with Glioblastoma on Conventional MRI

  The treatments of primary central nervous system lymphoma (PCNSL) and glioblastoma (GBM) are different; therefore, accurate diagnosis is crucial for the therapeutic planning. Although there is overlap of features on conventional magnetic resonance (MR) images between PCNSL and GBM, the PCNSL has specific features, which are different from those of GBM on conventional MR images. The current study aimed at characterizing specific features of PCNSL by comparing them with conventional MR images of GBM, and improving diagnostic accuracy at the time of initial presentation. Patients and The current study retrospectively evaluated the conventional MR images of 21 immunocompetent patients with PCNSL and 13 patients with GBM pathologically proven in Renmin Hospital of Wuhan University, Wuhan, China from January 2014 to March 2017. All patients were subjected to non-contrast and contrast enhanced MRI. Tumor location, quantity, and morphology, as well as common and specific features and patterns, peritumoral edema, and hemorrhage were recorded and compared. Twenty-one patients with PCNSL exhibited 44 lesions, and 13 patients with GBM exhibited 16 lesions. PCNSL affected both infra- and supratentorial regions, while GBM only affected supratentorial regions. Deep white matter, basal ganglia, periventricular areas, and the corpus callosum were the most common sites in PCNSL. Homogeneous enhancement was presented in 95.2% of PCNSL, and all GBM lesions showed heterogeneous enhancement. PCNSLs had various appearances, whereas most of the GBMs (81.3%) had a mass-like appearance. Differences in intratumoral hemorrhage (P < 0.001), necrotic or cystic components (P < 0.001), and intratumoral vascular enhancement (P < 0.001) between PCNSL and GBM were statistically significant. “Notch sign” and open-ring enhancement were specific features for PCNSL. PCNSL has specific features, patterns, and locations. These features and patterns can be helpful to differentiate PCNSL from GBM at the time of initial presentation