Model for Predicting Central Nervous System Relapse in Diffuse Large B-Cell Lymphoma and Discussion of Prophylaxis Measures

OBJECTIVE: Relapse of the central nervous system (CNS) is a rare but fatal complication in diffuse large B-cell lymphoma (DLBCL). The purpose of this study is to learn how to identify high-risk patients and take effective preventive measures.METHODS: We retrospectively analyzed 1,290 adult patients with DLBCL at Peking University Cancer Hospital and Shanxi Bethune Hospital between 2010 and 2020.RESULTS: There were 55 patients with CNS relapse who had a median follow-up of 5 years. The risk of CNS relapse was 1.58% in the low-risk group, 5.66% in the moderate risk group, and 11.67% in the high-risk group based on CNS International Prognostic Index (CNS-IPI). We found that CNS-IPI and testicular involvement were risk factors for CNS relapse, with OR 1.913 (95% CI: 1.036w3.531; P = 0.038) versus. OR 3.526 (95% CI: 1.335w9.313; P = 0.011), respectively. Intrathecal MTX and/or cytarabine prophylaxis was used in 166 patients (13.94%), intravenous (IV) high-dose methotrexate (HD-MTX) prophylaxis in 8 patients (0.67%), and intrathecal plus intravenous prophylaxis in 15 patients (1.26%). There was no significant difference in CNS relapse risk between IT, HD-MTX, and no prophylaxis recipients (12.7% vs. 0% vs. 23.6%, respectively, P = 0.170). The risk of CNS relapse was similar whether or not patients accepted prophylaxis (5-year risk 4.1% vs. 2.2%, P = 0.140). CONCLUSIONS: Central nervous system (CNS) relapse is associated with high risk CNS-IPI and testicular involvement. Therefore, it is necessary to pursue novel prophylactic strategies for CNS relapse.