Management of secondary central nervous system lymphoma: A British Society for Haematology Good Practice Paper

Secondary central nervous system (CNS) lymphoma (SCNSL) refers to lymphoma that has spread to the CNS concurrently with, or following treatment for, systemic lymphoma. There are three clinically distinct scenarios: Synchronous CNS and systemic lymphoma at initial presentation (treatment-naïve; TN-SCNSL), CNS relapse without recurrent systemic lymphoma (relapsed isolated CNS lymphoma; RI-SCNSL). Relapsed concomitant systemic and CNS disease following treatment for systemic lymphoma (RC-SCNSL). CNS lymphoma (CNSL) is associated with inferior outcomes, which may be attributed to several factors: poor CNS penetrance of chemotherapeutics, including RCHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisolone),1 impaired neurocognitive function and patient performance status (PS) contributing to increased treatment toxicity,2, 3 and recurrent genetic aberrations conferring treatment resistance.4-6 The rarity and heterogeneity of SCNSL also limits the evidence base for treatment recommendations, with poor outcomes potentially attributable at least in part to lack of optimised treatment protocols. This good practice paper focuses on diffuse large B-cell lymphoma (DLBCL), the most common SCNSL subtype. It covers diagnostic and therapeutic aspects of care for the three SCNSL scenarios and multiply relapsed SCNSL. Treatment recommendations are framed by patient fitness and treatment intent.