Intravenous busulfan-based conditioning with autologous stem cell transplantation for refractory B-cell lymphoma with central nervous system involvement.

The prognosis of relapsed or refractory lymphoma with central nervous system (CNS) involvement remains poor because of the lack of anticancer drugs with sufficient CNS penetration. [Case 1] A 65-year-old man was diagnosed with Stage IV mantle cell lymphoma. After two courses of chemotherapy and autologous hematopoietic stem cell (HSC) collection, urinary retention with fever developed. Cerebrospinal fluid analysis revealed leptomeningeal involvement, which was refractory to high-dose methotrexate therapy. Autologous peripheral blood stem cell transplantation (ASCT) was performed, followed by intravenous busulfan (ivBU), cyclophosphamide, and etoposide ; thereafter, no relapse has been detected for over six years. [Case 2] A 40-year-old woman with right lower hemiplegia was diagnosed with primary CNS lymphoma. Although four courses of high-dose methotrexate therapy were administered, the cerebral tumor increased in size. HSCs were collected after methotrexate therapy, and ASCT was performed in addition to conditioning using ivBU, cyclophosphamide, and etoposide, followed by whole-brain and local boost irradiation. She achieved complete remission, but relapsed two years after ASCT. High-dose ivBU-containing conditioning regimens with ASCT may be useful for refractory B-cell lymphoma with CNS involvement. J. Med. Invest. 68 : 196-201, February, 2021.