To evaluate the efficacy of high-dose methotrexate (HD-MTX, ≥1 g/m2) for the prevention of central nervous system (CNS) recurrence in patients with intravascular large B-cell lymphoma (IVLBCL), we reviewed 51 patients with pathologically diagnosed untreated IVLBCL. In total, there were five cases of CNS relapse (9.8%), and the 12-month CNS relapse rate was 9.2%. No statistical difference in CNS relapse rate (p = 0.86) was observed between patients with and without HD-MTX (n = 20 and 31, respectively). Furthermore, the composite endpoint defined as either CNS and/or neurolymphomatosis relapse was not significant in terms of the administration of HD-MTX (p = 0.25). No significant predictor of CNS relapse was found. In conclusion, patients with IVLBCL are at high risk of CNS recurrence; however, HD-MTX administration may not be effective for CNS recurrence prophylaxis. Key pointsThe administration of HD-MTX for patients with untreated IVLBCL may not be effective for preventing CNS relapse.
Keywords: Intravascular large B-cell lymphoma; central nervous system; high-dose methotrexate; recurrence.