Central nervous system relapse of lymphoid malignancies in adults: the role of high-dose chemotherapy.

Adults with CNS recurrence of lymphoid malignancies generally have a very poor prognosis. Although recent reports indicate that a proportion of patients may obtain prolonged remission after bone marrow transplantation, the role of high-dose chemotherapy in the management of this complication remains controversial. We reviewed the literature in order to better evaluate the relative contribution of high-dose chemotherapy to the outcome of patients with CNS recurrence. We focused mainly on results in adults, but included results on pediatric patients when relevant. Our review of the data indicates that 20% to 40% of adults with a history of CNS involvement by lymphoma or lymphoid leukemia can be cured by high-dose chemotherapy. A small fraction of patients with active CNS involvement can be cured as well. No data is available to determine superiority of a particular conditioning regimen or of allogeneic vs. autologous BMT. There is no conclusive benefit to post-transplant intrathecal therapy and the role of cranial or cranio-spinal radiation treatment and its optimal timing remains to be determined. Prospective studies are needed to resolve many of the issues regarding the treatment, and to improve the outcome of patients with CNS recurrence of lymphoid malignancies.