MR findings of intravascular large B-cell lymphoma of the central nervous system: report of three cases.

Background: Intravascular large B-cell lymphoma (IVLBCL) of the central nervous system (CNS) is a rare subtype of diffuse large B-cell lymphoma. Diagnosing CNS-limited IVLBCL is particularly challenging due to its non-specific clinical presentation and laboratory findings. We present three cases of CNS-limited IVLBCL, expanding the understanding of its imaging spectrum and enhancing preoperative diagnostic accuracy.

Case Report: Case 1 involved a 58-year-old male presenting with mild neurological symptoms, initially misdiagnosed as cerebrovascular disease. MRI showed patchy areas of diffusion restriction adjacent to the posterior horn of the left lateral ventricle, progressing over four months to a patchy hemorrhagic lesion in the right temporoparietal region with leptomeningeal enhancement. Case 2 described a 53-year-old male with progressive limb weakness and cognitive decline, initially managed as a demyelinating disease. MRI demonstrated extensive white matter hyperintensities and multiple areas of diffusion restriction. Case 3 involved a 67-year-old female with recurrent cognitive decline and gait disturbance. MRI findings included patchy T2 hyperintensities in the white matter, gyrus-like hyperintensity on T1WI, and punctate and linear enhancement. Cases 1 and 2 were diagnosed as IVLBCL post-biopsy, while in Case 3, IVLBCL was considered based on imaging features and differentiated from CNS vasculitis.

Conclusion: These cases highlight the variable and often non-specific MRI characteristics of CNS-IVLBCL, including infarct-like lesions, persistent diffusion restriction, and SWI abnormalities. Early recognition of these imaging findings can aid in timely diagnosis and treatment, potentially improving patient outcomes.