Treatment outcome of relapsed/refractory primary central nervous system diffuse large B-cell lymphoma: a single-center experience of autologous stem cell transplantation.

No salvage treatment strategy has been established for relapsed or refractory primary central nervous system lymphoma (PCNSL). We compared treatment outcomes of patients who underwent salvage chemotherapy with or without autologous stem cell transplantation (ASCT). We retrospectively analyzed PCNSL patients who were histologically diagnosed with diffuse large B-cell lymphoma. All patients relapsed after high-dose methotrexate (MTX)-based chemotherapy, or were refractory to high-dose MTX. Patients were treated with salvage chemotherapy, such as ICE/D (ifosfamide, carboplatin, etoposide, and dexamethasone) or high-dose MTX. High-dose chemotherapy containing thiotepa and busulfan followed by ASCT was performed if patients were eligible for ASCT after salvage treatment. Forty-five patients (35 relapsed and 10 refractory) received ICE/D or high-dose MTX. Despite the important difference that ICE/D was used predominantly for early relapsed or refractory patients, the two salvage treatments produced similar overall response rates [84.4 % (38/45) for ICE/D and 81.3 % (13/16) for high-dose MTX re-treatment]. Eighteen patients underwent ASCT, whereas 27 patients received salvage chemotherapy alone. The median progression-free survival of patients who underwent ASCT (19.5 months) was significantly better than that of patients who did not receive ASCT (6.7 months, P = 0.023). Multivariate analysis showed that refractoriness to initial treatment and no ASCT were significantly associated with poor survival outcome. Our study suggested that the combination of ifosfamide, carboplatin, etoposide, and dexamethasone may represent a feasible salvage treatment option for relapsed or refractory PCNSL, and that high-dose chemotherapy containing thiotepa and busulfan followed by ASCT may be effective for patients with a favorable toxicity profile.