Clinical analysis of patients with primary and secondary extranodal natural killer/T-cell lymphoma of central nervous system.

Extranodal natural killer (NK)/T-cell lymphoma (NKTL) is a rare non-Hodgkin lymphoma that rarely arise exclusively in or metastasizes to the central nervous system (CNS). Globally, CNS involvement of NKTL heralds a serious prognosis and there is no standard treatment. 19 of 414 patients (4.59%) with ENKL followed were diagnosed with CNS involvement between 2006 and 2020. Two patients had primary CNS (PCNS) NKTL, and 17 patients had secondary CNS (SCNS) invasion. A total of 9 patients survived and 10 patients died. The median overall survival time was 55 months, and the median survival time after CNS invasion was 17 months. The 5-year cumulative survival probability was 45.7%. In conclusion, CNS risk evaluation and prophylaxis treatment can be carried out for patients with NK/T-cell lymphoma prognostic index risk group III/IV. In terms of treatment, systemic therapy based on methotrexate combined with radiotherapy and intrathecal chemotherapy can be selected.