Enhancement pattern of demyelination‐mimicking cerebral B‐cell lymphoma

Abstract

Background and purpose Central nervous system (CNS) B‐cell lymphoma‐mimicking demyelinating diseases creates a diagnostic dilemma. This study aimed to determine the specific magnetic resonance imaging (MRI) features of CNS B‐cell lymphoma to facilitate the early identification of the disease. Methods We retrospectively reviewed the brain MRI of biopsy‐confirmed CNS B‐cell lymphoma patients. They were initially diagnosed with CNS demyelination, and these images were compared with those of actual patients with demyelinating diseases. Results A total of 20 patients with CNS B‐cell lymphoma and 12 patients with demyelination were included in this study. Cohesive enhancement with satellite enhancing foci surrounded by prominent non‐enhancing areas of oedema is the major contrast‐enhancing pattern of lymphoma patients, accounting for 81% (13) of patients with primary diffuse large B‐cell lymphoma (DLBCL). This imaging pattern revealed a sensitivity of 81% and a specificity of 75% for lymphoma in the differential diagnosis between primary DLBCL and demyelinating disease in our cohort. Among these lesions, most of the nodules were located deeply, which yielded a specificity of 100% and a sensitivity of 69% for primary DLBCL. Enhancement in a single pattern (mainly ring‐like, patchy or punctate; 57%) and no enhancement (30%) were commonly observed in demyelinating lesions, distinct from primary DLBCL (p < 0.05). Conclusions Lesions with cohesive enhancement and satellite foci on T1 contrast‐enhanced imaging could be a specific hallmark of CNS B‐cell lymphoma, suggesting the need to withdraw steroidal therapy and biopsy confirmation.