A retrospective study at a single center examining risk factors associated with central nervous system involvement in individuals diagnosed with diffuse large B-cell lymphoma

Objective

The aim of this study is to identify risk factors contributing to central nervous system (CNS) invasion and to validate the suitability of the Central Nervous System International Prognostic Index (CNS-IPI) for individuals afflicted with diffuse large B-cell lymphoma (DLBCL).

Methods

Based on the presence or absence of CNS invasion, 365 patients were stratified into two groups: the CNS group and the non-CNS group. The clinical data of the patients were retrospectively analyzed using univariate and multivariate analysis, and the differences in survival curves were compared. The dependent variable in this study was the presence or absence of CNS invasion, while the independent variables included age, stage, extranodal involvement, renal/adrenal involvement, and others. Statistical methods included the chi-squared test and Fisher’s exact test for intergroup comparison and binary logistic regression for multi-factor analysis. The related risk factors were modeled using the Cox proportional hazards model. The Kaplan–Meier method was used to generate survival curves, and the log-rank test was used to compare the differences between survival curves. The optimal cutoff value of beta-2 (β2)-microglobulin was determined through the utilization of a receiver operating characteristic (ROC) curve. All P values were bidirectional, and P < 0.05 was considered statistically significant. Both SPSS 23.0 (IBM Inc., Armonk, NY, USA) and RStudio (R software version 4.0.2, R Project for Statistical Computing) software were used for data processing

Results

The five factors of the CNS-IPI were related to the prognosis of patients with CNS invasion. Bone involvement, albumin < 40 g/L, and P53 protein (+) were the risk factors for CNS invasion in patients with DLBCL. However, prognostic factors such as double strike, testicular involvement, breast involvement, uterine involvement, and bone marrow involvement did not apply to these patients. It was also discovered that elderly patients with DLBCL with reduced albumin levels were more susceptible to CNS invasion. Furthermore, extranodal involvement at multiple sites and elevated beta-2 (β2) microglobulin were independent prognostic factors

Conclusion

Patients older than 60 years with DLBCL and decreased albumin are at increased risk for CNS invasion. In addition to the five factors in the CNS-IPI, bone involvement, albumin levels < 40 g/L, and P53 protein expression are risk factors affecting the prognosis of CNS invasion in patients with DLBCL.