Significance of treatment response when managing patients with primary central nervous system lymphoma

First-line induction chemotherapy with high-dose methotrexate versus teniposide in patients with newly diagnosed primary central nervous system lymphoma: a retrospective, multicenter cohort study

BACKGROUND

This study aimed to compare the efficacy and safety of high-dose methotrexate (HD-MTX) versus teniposide (TEN) in patients with newly diagnosed immunocompetent primary central nervous system lymphomas (PCNSLs).

METHODS

The study included immunocompetent, adult patients with newly diagnosed PCNSL at 22 centers in China from 2007 to 2016. The patients received HD-MTX or TEN as first-line induction therapy. The objective response rate, progression-free survival, and overall survival were analyzed for each patient cohort.

RESULTS

A total of 96 patients were eligible: 62 received HD-MTX, while 34 received teniposide. The overall response rate was 73.2% and 72.7% in the MTX and the TEN cohorts, respectively (P = 0.627). The median progression-free survival was 28.4 months [95% confidence interval (CI): 13.7-51.2] in the MTX cohort and 24.3 months (95% CI: 16.6-32.1) in the TEN cohort (P = 0.75). The median overall survival was 31 months (95% CI: 26.8-35.2) in the MTX cohort and 32 months (95% CI: 27.6-36.4) in the TEN cohort (P = 0.77). The incidence of any grade of coagulopathy/deep-vein thrombosis and gastrointestinal disorders was significantly higher in the MTX cohort than in the TEN cohort; no significant difference was found in the incidence of other adverse events between the two cohorts.

CONCLUSIONS

This was the first multicenter study using TEN as the main agent compared with HD-MTX in newly diagnosed primary CNS lymphoma. The TEN-based regimen was non-inferior to the HD-MTX-based regimen with similar overall responses.

CLASSIFICATION OF EVIDENCE

This study provided Class III evidence that the teniposide-based regimen was non-inferior to high-dose methotrexate - based regimen with similar overall responses and long-time survival in immunocompetent patients with PCNSL.

Advances and challenges in the treatment of primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL), a rare variant of non-Hodgkin's lymphoma, is characterized by distinct biological characteristics and clinical behaviors, and patient prognosis is not satisfactory. The advent of high-dose (HD) methotrexate (HD-MTX) therapy has significantly improved PCNSL prognosis. Currently, HD-MTX-based chemotherapy regimens are recognized as first-line treatment. PCNSL is sensitive to radiotherapy, and whole-brain radiotherapy (WBRT) can consolidate response to chemotherapy; however, WBRT-associated delayed neurotoxicity leads to neurocognitive impairment, especially in elderly patients. Other effective approaches include rituximab, temozolomide, and autologous stem-cell transplantation (ASCT). In addition, new drugs against PCNSL such as those targeting the B-cell receptor signaling pathway, are undergoing clinical trials. However, optimal therapeutic approaches in PCNSL remain undefined. This review provides an overview of advances in surgical approaches, induction chemotherapy, radiotherapy, ASCT, salvage treatments, and novel therapeutic approaches in immunocompetent patients with PCNSL in the past 5 years. Additionally, therapeutic progress in elderly patients and in those with relapsed/refractory PCNSL is also summarized based on the outcomes of recent clinical studies.