Primary central nervous system lymphoma treatment
Newly diagnosed PCNSL patients should be treated with combined high-dose methotrexate-based regimen and can be treated with a rituximab-inclusive regimen at induction therapy. Autologous stem cell transplantation can be used as a consolidation therapy. Refractory or relapsed PCNSL patients can be treated with ibrutinib with or without high-dose chemotherapy as re-induction therapy. Stereotactic radiosurgery can be used for PCNSL patients with a limited recurrent lesion who were refractory to chemotherapy and have previously received whole-brain radiotherapy. Primary vitreoretinal lymphoma (PVRL) or PCNSL patients with concurrent VRL can be treated with combined systemic and local therapy 1)
A study described a new miR-370-mediated mechanism of MGMT regulation in PCNSL.
Li et al., first showed that miR-370 was downregulated in PCNSL tissues, while MGMT was inversely overexpressed. It was also observed that miR-370 suppressed the expression of MGMT. Additionally, upregulation of miR-370 significantly increased TMZ sensitivity dependent of MGMT, thus suppressed Raji cell proliferation and induced apoptosis in vitro. In conclusion, these results suggest that miR-370 is a potential target in PCNSL treatment 2).
In a retrospective study, the aim was to analyze the outcome in PCNSL patients treated with the combination of Rituximab, methotrexate (MTX), cytarabine (Ara-C) and dexamethasone (R-MAD). Eighteen patients from Beijing Tiantan Hospital (Beijing, China) between January 2010 and March 2014 were newly diagnosed with PCNSL [diffuse large B-cell lymphoma (DLBCL) type] and received R-MAD as first-line treatment. The dosage was as follows: 375 mg/m2 Rituximab was administered on day 0, 3.5 g/m2 MTX was administered on day 1, 1 g/m2 Ara-C was administered on day 2 and 10 mg dexamethasone was administered on days 1-3, every 3 weeks. After 6 cycles, the overall response rate was 94.5%. Ten (55.6%) patients achieved complete response (CR), 7 (38.9%) achieved partial response (PR) and 1 (5.6%) had progressive disease (PD). Patients were followed up from the start of the treatment, median 24.2 months (range 6-48). The overall survival (OS) rate was 94.5% and progression-free survival rate was 94.5%. The median OS was 22 months (95% confidence interval, 19.4-24.6). The high level of serum lactate dehydrogenase (LDH) concentration was associated with a poor outcome. Among 5 patients with an abnormally high LDH concentration, 1 achieved CR, 3 had PR and 1 had PD. None of the patients experienced any grade 4 toxicity. These results indicated that the R-MAD immunochemotherapy regimen is effective in PCNSL patients without serious toxicity. A prospective investigation with more patients should be administered in order to understand the more accurate effect of the regimen 3).