Risk of death, relapse or progression, and loss of life expectancy at different progression-free survival milestones in primary central nervous system lymphoma.

In this study, we analyzed the evolution of the prognosis of primary central nervous system lymphoma (PCNSL) patients as they reach selected progression-free survival (PFS) milestones after high-dose methotrexate (HD-MTX)-based therapy. In total, 258 and 146 patients were included from Denmark and British Columbia, respectively. All patients were diagnosed during 2000-2017. The 5-year PFS was 27% (95% CI 23; 32); however, for patients reaching 5 years of PFS, this increased to 71% (95% CI 57; 86). Within the first 5 years after diagnosis, patients lost 2.0 years (95% CI 1.8; 2.2) when compared to a similar background population. This reduced to 0.5 years (95% CI 0.2; 0.9) for patients reaching 5 years of PFS. Treatment with rituximab was associated with improved outcomes. The prognosis of patients with PCNSL treated with HD-MTX-based regimens in this cohort is poor, although it improves as patients survive without progression/relapse. However, survival does not conclusively normalize to that of a similar background population.