Overall survival rates for primary central nervous system lymphoma (PCNSL) have increased significantly over the last four decades thanks to prompt treatment initiation and the use of intensive high-dose methotrexate and rituximab-based protocols, a UK study shows.

The observational study was based on patient data from Nottingham University Hospitals Trust, split into two distinct therapeutic eras: 1982 to 2010 (era 1; 147 patients), and 2011 to July 2020 (era 2; 125 patients).

Led by clinical haematologist Dr Furqaan Kaji, the research team found that the median age at PCNSL diagnosis was significantly older in the second era (69 years) versus the first (65 years), while the proportion of patients aged over 70 years at the treatment centre had also risen over the two timeframes (424% versus 245%, respectively).

However, overall survival (OS) rates were found to be significantly higher in the second era than in the first – 85% vs 56% at 3 months, 77% vs 49% at 6 months and 62% vs 38% at 12 months, respectively – and data showed a “pronounced reduction in the risk of early death”, the authors said.

The use of intensive high-dose methotrexate (HD-MTX) protocols (including consolidation with high-dose chemotherapy and autologous stem cell transplantation) made an impact on OS in the second era compared to non-intensive HD-MTX schedules (HR 0.47, 95% CI 0.22–0.99).

However, the authors noted the potential for inherent selection bias given that intensively treated patients were generally younger and fitter.

Starting chemotherapy within 14 days of biopsy and the use of rituximab in treatment strategies were also linked to improved overall and progression free survival in the second era, the study authors noted in the paper published in the British Journal of Haematology.

Overall, “the data suggest that prompt treatment initiation and use of intensive HD-MTX and rituximab-based protocols have resulted in improved survival outcomes for patients,” the authors concluded.

“Importantly, for all patients, we highlight the imperative for rapid initiation of therapy after diagnostic biopsy, an observation which should inform the design and implementation of modern clinical pathways for PCNSL diagnosis and management,” they added.

Disclosure: One of the paper’s authors, Christopher P. Fox, has received research funding and consultancy fees from Roche and Adienne