▪BackgroundPrimary central nervous system lymphoma (PCNSL) is a rare non-Hodgkin lymphoma (NHL) and counts for about 3% of all CNS neoplasms. Despite advances in treatment, patients' overall survival (OS) is still disastrous. Several prognostic factors have been reported (Ferreri et al . J Clin Oncol. 2003; Abrey et al . J Clin Oncol. 2006; Kreher et al . Ann Hematol. 2015), including age, performance status, serum lactate dehydrogenase, CSF protein level, involvement of deep brain, and intraocular involvement. In the present study, we investigated the risk factors of disease progression and purposed to integrate them into a scoring system for PCNSL.MethodsWe enrolled newly diagnosed PCNSL patients at a national medical center in Taiwan between January 1, 2002 and December 31, 2015. Patients without histological confirmations, or those diagnosed with secondary CNS lymphoma or AIDS were excluded. The cohort was followed up until the end of February, 2017. The risk factors of disease progression and death were identified using univariate and multivariate Cox proportional hazards models. The independent predictors were assigned a value of either 0, if favorable, or 1, if unfavorable, in a prognostic model for risk stratification.ResultsThe study cohort consisted of 101 PCNSL patients, with a median age of 64 years. The median progression-free survival (PFS) and OS were 17.3 (95% confidence interval [CI] 8.4-21.7) months and 100.8 (95% CI 29.5 to not reached) months, respectively. In the multivariate analysis, age ≥ 80 (adjusted hazards ratio [HR] 2.46, 95% CI 1.22-4.99, p= 0.012), involvement of deep brain (adjusted HR 2.57, 95% CI 1.39-4.72, p= 0.003) and ECOG performance status ≥ 2 (adjusted HR 1.87, 95% CI 1.09-3.20, p= 0.024) were identified as independent risk factors of disease progression. The patients were divided into four groups based on the independent predictors. The Kaplan-Meier survival analysis showed the patients with a higher prognostic score had a shorter PFS (log-rank p < 0.001) and OS (log-rank p= 0.005; Figure 1).ConclusionWe identified age ≥ 80, involvement of deep brain, and ECOG ≥ 2 as independent risk factors of disease progression in the PCNSL patients. Our new scoring system demonstrates a good risk stratification for PFS and OS in patients with PCNSL. Identifying patients at a higher prognostic score may help clinicians initiate appropriate management and early treatment. Further validation of our findings in other cohorts is warranted. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.