Efficacy and Toxicity of Treatments for Primary Central System Lymphoma: Review of the Recent Literature

Résumé

Primary Central Nervous system lymphoma (PCNSL) is an uncommon type of central nervous system lymphoma, most commonly presenting as hemiparesis and headache. Currently, there is a wide range of treatments for PCNSL, consisting of various permutations between chemotherapy, radiation and autologous stem cell transplant (ASCT). Although the backbone of PCNSL treatment consists of High-dose Methotrexate (HD-MTX), the role of combination versus single agent chemotherapy, combined modality (chemotherapy + radiation) versus chemotherapy or radiation alone, and the use of consolidative ASCT are contested. Surgery does not have a role in the treatment of PCNSL although stereotactic biopsies tend to help with symptomatic relief. Radiation monotherapy is generally reserved for patients with contraindications to chemotherapy or as a palliative measure. Combined chemotherapy and radiation treatment has been shown to have a great efficacy, although its increased neurotoxicity compared to chemotherapy alone is a major drawback. A growing body of research is focused on comparing the efficacy of various chemotherapeutic regimens. Currently, the MATRix regimen comprising of HD-MTX(3.5g/m²)-cytarabine/rituximab/thiotepa is widely used. The additional survival benefit of ASCT is contested although its role in the treatment of refractory or relapsed PCNSL is generally agreed upon. Finally, intrathecal HD-MTX has been shown to have added survival benefit when added to the standard therapies. Further retrospective and prospective studies are required to compare the efficacy and toxicity of various treatment options, with a focus on different chemotherapeutic agents and ASCT.