Central nervous system involvement in intravascular large B‐cell lymphoma: A retrospective analysis of 109 patients

Intravascular large B-cell lymphoma (IVLBCL) is a rare disease entity with a high incidence of central nervous system (CNS) involvement at diagnosis. To evaluate CNS involvement, particularly recurrence including progression on therapy and relapse of IVLBCL, we retrospectively analyzed 109 patients with IVLBCL receiving chemotherapies with or without rituximab. In 82 patients (75%) without CNS involvement at initial diagnosis, risk of CNS recurrence at 3 years was 25% with a median follow-up in survivors of 39 months (range, 2-158 months). In 27 patients (25%) with CNS involvement at initial diagnosis, risk of CNS recurrence at 1 year was 25% with a median follow-up in survivors of 18 months (range, 10-77 months). Duration from diagnosis to CNS recurrence tended to be short in patients with CNS involvement at diagnosis. No significant difference in risk of CNS recurrence was found between patients receiving chemotherapies with or without rituximab. On multivariate analysis skin involvement at initial diagnosis was identified as a predictive factor for CNS recurrence in patients without CNS involvement at diagnosis (hazard ratio, 5.27; 95% confidence interval, 1.59-17.4; P = 0.007). Survival rate after CNS recurrence at 2 years was 12% in patients without CNS involvement at diagnosis. Central nervous system recurrence is a serious complication in IVLBCL patients and optimal strategies for CNS involvement should be established to obtain further improvements to clinical outcomes in the rituximab era.