High-dose methotrexate, etoposide, dexamethasone and pegaspargase (MEDA) combination chemotherapy is effective for advanced and relapsed/refractory extranodal natural killer/T cell lymphoma: a retrospective study

Extranodal natural killer/T cell lymphoma, nasal type (ENK/TCL), is an aggressive and rare hematological malignancy. Patients with advanced and relapsed/refractory disease have very poor outcomes. In this study, we retrospectively assessed the efficacy and safety of MEDA regimen (methotrexate, etoposide, dexamethasone and pegaspargase) in the treatment of advanced and relapsed/refractory ENK/TCL patients. Thirteen patients received a total of 55 cycles of MEDA, with a median of four cycles. At the completion of treatment, the overall response rate was 76.9 %, with a complete response rate of 61.5 %. The 1-year overall survival rate was 69.2 %, and 1-year progression-free survival was 61.5 %. Treatment-related toxicity was monitored in all patients. Grade 3/4 neutropenia occurred in 46.2 % of patients. Serious infections happened in two cases (15.4 %). Grade 3/4 thrombocytopenia occurred in 30.8 % of patients, and 23.1 % received platelet transfusion. Grade 3/4 anemia was observed in 23.1 % of patients. Hepatotoxicity and low fibrinogen were common, but mild. These results show that MEDA regimen is very effective with tolerable adverse effects in the treatment of advanced and relapsed/refractory ENK/TCL. Further prospective trials are expected to validate the efficacy of MEDA in an expanded number of patients.