Multiply Relapsed Secondary CNS Non-Germinal Center Diffuse Large B-Cell Lymphoma Successfully Treated with CNS-Centric Therapy.

Secondary central nervous system involvement by systemic diffuse large B-cell lymphoma (DLBCL) carries a very poor prognosis. We present a female patient who had two episodes of intracerebral central nervous system (CNS)-only relapse of systemic non-germinal center diffuse large B-cell lymphoma (NGC-DLBCL). Her treatment at initial diagnosis consisted of induction with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) and intrathecal (IT) - methotrexate (MTX) followed by consolidation with autologous stem cell transplant (ASCT) after high-dose carmustine, etoposide, cytarabine, and melphalan (BEAM) chemotherapy. She had the first CNS-only relapse 1.5 years post-ASCT and received whole brain radiation therapy (WBRT). She developed the second intracerebral CNS-only relapse 2 years post-WBRT. A CNS-centric therapeutic approach with salvage chemoimmunotherapy incorporating rituximab, high-dose methotrexate (HD-MTX), high-dose cytarabine (HiDAC), and ibrutinib was utilized for her second CNS-only relapse. She underwent consolidation with a second ASCT following high-dose carmustine (BCNU) and thiotepa chemotherapy. Given her high risk of CNS recurrence, she was started on maintenance ibrutinib. To date, she has remained in complete remission for 3 years. In our experience, multiply relapsed secondary CNS lymphoma (SCNSL) with this response is very rare. We suggest one CNS-centric therapeutic approach that can potentially salvage patients with SCNSL who have not had prior exposure to adequate CNS-directed therapies but acknowledge that additional research is necessary to validate our findings.