Radiotherapy Followed by DICEP Regimen in Treatment of Newly Diagnosed, Stage IE/IIE, Extranodal NK/T-cell Lymphoma Patients

Background: The optimal treatment strategies for extranodal natural killer/ T-cell lymphoma (ENKTL) have not been defined. We conducted this prospective, open-label, phase II, single-center study aimed to explore the efficacy and safety of radiotherapy followed by DICEP (Dexamethasone, ifosfamide, cisplatin, etoposide, and pegaspargase) regimen in the treatment of patients with untreated, stage IE/IIE, extranodal NK/T-cell lymphoma.

Methods: Thirty eligible patients were enrolled in this study, receiving radiotherapy of 50Gy/25fx, and followed by chemotherapy with DICEP regimen for 3 cycles if tolerated. Median follow-up time of this study was 70.8 months. We constructed Kaplan-Meier survival curves for survival analyses.

Results: The most common manifestations at the onset of disease were nasal obstruction (80%), with or without fever, and pharyngalgia (20%). The overall response rate (ORR) was 96.7% (29/30). Four patients (13.3%) had progression of the disease (PD), the estimated 5-year progression-free survival (PFS) rate was 86%. Four patients (13.3%) died of disease, and the estimated 5-year cumulative overall survival (OS) was 87%. The most common hematological toxicity was grade 3 or grade 4 neutropenia, which could be successfully managed via using growth-stimulating factors or dose modifications. Hypoalbuminemia and decreased fibrinogen are the top two nonhematologic toxicities. No treatment-related death occurred in this study.

Conclusions: Our present study showed that radiotherapy followed by DICEP chemotherapy could be an effective and tolerable treatment modality for newly diagnosed, stage IE/IIE ENKTL patients. Adverse events were predictable and manageable.

Trial Registration: ClinicalTrials.gov Identifier: NCT01667302. Registered: 1 July 2012.