Primary CNS Lymphoma: Is Abscece of Intratumoral Hemorrhage a Characteristic Finding on MRI
Background and aim: Previous studies have shown that intratumoral hemorrhage is a common finding in glioblastoma multiforme (GBM), but is rarely observed in primary central nervous system lymphoma (PCNSL). Our aim was to reevaluate whether intratumoral hemorrhage observed on T2-weighted imaging (T2WI) as gross intratumoral hemorrhage (GITH) and on susceptibility-weighted imaging (SWI) as an intratumoral susceptibility signal (ITSS) can differentiate PCNSL from GBM.
Methods: A retrospective cohort of brain tumors from August 2008 to March 2013 was searched, and 58 patients (19 PCNSL, 39 GBM) satisfied the inclusion criteria. Absence of GITH was examined on T2WI, and ITSS was graded using a 3-point scale on SWI. Results were compared between PCNSL and GBM, and values of P < .05 were considered significant.
Results: GITH on T2WI was absent in 15 patients (79%) with PCNSL and 23 patients (59%) with GBM. Absence of GITH could not differentiate between the two disorders (P = 0.20). However, ITSS grade 1 or 2 was diagnostic of PCNSL with 79.0% sensitivity and 67.5% specificity (P < 0.0001), irrespective of GITH.Conclusions: Low ITSS grades can differentiate PCNSL from GBM. However, specificity in this study was relatively low, and PCNSL cannot be excluded based solely on the presence of an ITSS.