Treatment of primary CNS lymphoma (PCNSL) following successful treatment of systemic non-Hodgkin's lymphoma (NHL): a case series.

Management of PCNSL occurring after successful treatment of systemic non-Hodgkin's lymphoma (NHL) is poorly defined. Illustrate a treatment approach for PCNSL following prior treatment of a systemic NHL. A retrospective case series of 6 patients (mean age 60 years; range 46-65) diagnosed with a diffuse large B cell lymphoma of the CNS following prior successful treatment of a systemic NHL (low-grade in 2; high-grade in 4). Mean interval to diagnosis of PCNSL after diagnosis of systemic NHL was 12 months (range 7-18). In 4/6 patients in whom genetic analysis could be performed, the PCNSL and NHL differed. Treatment utilized high-dose methotrexate and rituximab (immunochemotherapy) followed in patients with a radiographic complete response by autologous peripheral stem cell transplant (ASCT) with total body irradiation (TBI) and multi-agent conditioning chemotherapy (BEAM: carmustine, etoposide, cytarabine, melphalan). 5/6 patients had a radiographic complete response to immunochemotherapy and were treated with ASCT. 4/5 patients were free of disease following ASCT with a mean follow-up of 3 years (range 0.5-4 years). There were no toxic deaths and all patients transplanted successfully engrafted within 28 days (mean 18). Using a treatment paradigm similar to that utilized for recurrent systemic NHL (induction chemotherapy followed by ASCT) for PCNSL occurring metachronously after successful treatment of systemic NHL appears safe and effective.