Iatrogenic immunodeficiency-associated lymphoproliferative disorders of the central nervous system: a treatment paradox.

Abstract

Primary central nervous system lymphomas (PCNSLs) have historically had dismal survival rates until the advent of high-dose methotrexate (HD-MTX) based chemotherapy regimens. With increasing prevalence of autoimmune disease and development of new immunosuppressants, a genetically distinct entity known as iatrogenic immunodeficiency-associated lymphoproliferative disorder (LPD) has emerged. Many of these cases arise following methotrexate use, challenging feasibility of standard HD-MTX regimens. The aim of this study was to further characterize this disorder and determine the optimal management strategy. We describe a case of a 76-year-old female with iatrogenic immunodeficiency-associated PCNSL successfully treated with surgical resection followed by an antiviral and rituximab based regimen. We then performed a systematic literature review and identified 58 cases of non-transplant iatrogenic immunodeficiency-associated LPD involving the CNS. We used a linear probability statistical model to determine correlations with outcome. Natalizumab was associated with EBV negative tumors (P=.023), and EBV positive tumors were associated with improved outcomes (P=.016). Surgical resection was associated with improved outcomes (P=.032), although limited by potential confounding effect. Antiviral treatment (P=.095), rituximab (P=.111), and stem cell transplant (SCT) (P=.198) showed a trend toward improved outcomes. The remaining treatments including methotrexate showed no improvement. We propose that surgical resection, rituximab, and antiviral treatment may be considered as an alternative to standard HD-MTX based regimens when managing iatrogenic immunodeficiency-associated LPD of the CNS. Further study through prospective cohort studies or randomized clinical trials is warranted.