Clinical presentation, treatment, and outcomes of patients with central nervous system involvement in extranodal natural killer/T-cell lymphoma.

Extranodal natural killer (NK)/T-cell lymphoma (ENKTCL) is a rare type of Non-Hodgkin's lymphoma which rarely metastasizes to the central nervous system (CNS). Ten of 60 patients (16.7%) with ENKTCL followed at Memorial Sloan Kettering Cancer Center (MSKCC) were diagnosed with CNS involvement between 1995 and 2016. Eight patients had systemic disease at the time of CNS diagnosis; one patient never developed systemic disease and another was in remission at the time of CNS relapse. Median overall survival was 3.8 months; at time of this report 9 patients have died and one who underwent autologous stem cell transplant (ASCT) is alive 27 months after CNS diagnosis. Five patients achieved a complete response in the CNS; one is still alive, one died of systemic disease, and three died of infection. CNS ENKTCL portends a grim prognosis, with no standard treatment. Prospective study on ASCT and immunotherapy in CNS ENKTCL is warranted.