Efficacy of a pegaspargase-based regimen in the treatment of newly-diagnosed extranodal natural killer/T-cell lymphoma.

Extranodal natural killer (NK)/T-cell lymphoma (ENKL) is an aggressive neoplasm with poor prognosis. Currently, there is no consensus on the optimal treatment of this disease. In this study, we report the efficacy of a pegaspargase (PEG-Asp)-based chemotherapy, a DDGP regimen (PEG-Asp, dexamethasone, cisplatin, gemcitabine), for the treatment of newly-diagnosed ENKL. From August 2010 to May 2012, 12 patients with newly-diagnosed stage II - IV ENKL were initially treated with a DDGP regimen in our center. Ten patients (10/12, 83.3%) achieved complete response (CR) and two (2/12, 16.7%) achieved partial response (PR). The objective overall response rate (ORR) was 100%. Three patients (3/12, 25.0%) relapsed, and as a result, two died of disease. Eight patients (8/12, 66.7%) were alive with no evidence of disease (NOD) after a median follow-up of 19 months (range 16 - 31 months). Hematologic toxicity was the most frequent toxicity reported in this study. Grade 3/4 leukopenia and neutropenia were common and both occurred in eight patients (8/12, 66.7%), respectively. Additionally, six patients (6/12, 50.0%) experienced grade 3/4 thrombocytopenia and three (3/12, 25.0%) experienced grade 3/4 anemia. However, no patient died of hematologic toxicity. Our results demonstrate the significant efficacy and safety profile of a DDGP regimen in the treatment of newly-diagnosed ENKL, and indicate the potential of this regimen as a first-line therapy against this disease.