From the Guidelines
Intravenous high-dose methotrexate is the most effective strategy for preventing CNS relapse in high-risk patients with diffuse large B-cell lymphoma, and its use should be prioritized in patients with CNS lymphoma without visible tumors. When considering the management of CNS lymphoma without visible tumors, it's crucial to focus on preventing relapse and improving outcomes. According to a recent systematic review and meta-analysis published in Haematologica 1, intravenous high-dose methotrexate has been shown to be effective in preventing relapse to the central nervous system in high-risk patients. Key points to consider in the management of CNS lymphoma without visible tumors include:
- The use of intravenous high-dose methotrexate as the backbone therapy, given its efficacy in preventing CNS relapse 1
- The potential addition of other agents like rituximab, cytarabine, or temozolomide to the treatment regimen, depending on the patient's specific needs and risk factors
- The importance of regular monitoring with MRI scans and CSF analysis to assess treatment response and detect any potential relapse early
- The consideration of whole-brain radiation therapy in some cases, although its use is often deferred due to concerns about neurotoxicity
- The need for a multidisciplinary team approach, including neuro-oncologists, hematologists, and radiation oncologists, to manage this complex condition effectively.
From the Research
CNS Lymphoma Without Tumors
- Primary central nervous system lymphoma is a diffuse large B-cell lymphoma with exclusive manifestation in the central nervous system (CNS), leptomeninges, and eyes 2.
- The incidence of primary CNS lymphoma is 0.5 per 100 000 persons per year, and its clinical and neuroradiological presentation is often nonspecific, requiring histopathological confirmation 2.
- Treatment for primary CNS lymphoma typically consists of high-dose chemotherapy based on methotrexate (HD-MTX) combined with rituximab and other cytostatic drugs that penetrate the blood-brain barrier 2, 3.
- Long-term survival can be achieved in patients under age 70 by adding non-myeloablative consolidation chemotherapy or high-dose chemotherapy with autologous stem cell transplantation (HD-AST) to the induction therapy 2, 3.
- Some studies suggest that chemoimmunotherapy with methotrexate, cytarabine, thiotepa, and rituximab (MATRix regimen) can be an effective treatment for primary CNS lymphoma, with a complete remission rate of 49% 4.
- Evidence-based management of primary CNS lymphoma recommends intensive high-dose methotrexate-containing induction followed by consolidation with autologous stem cell transplantation with thiotepa-based conditioning for fit patients 5.
- Less intensive chemoimmunotherapy, novel agents, and whole brain radiotherapy may be reserved for less fit patients or disease which is chemoresistant 5, 6.
- The risk of neurotoxicity is lower in patients treated with chemotherapy alone, and whole-brain radiation therapy (WBRT) alone is insufficient for durable tumor control and is associated with a high risk of neurotoxicity in patients older than age 60 6.