Long-Term Outcomes of Patients with Newly Diagnosed NK/T-Cell Lymphoma Treated by EPOCH Regimen.

Extranodal NK/T-cell lymphoma (ENKL) is a distinct clinicopathological entity of non-Hodgkin's lymphoma, which is characterized by a highly aggressive clinical process and poor prognosis. There are no standard treatment strategies available now. The present study aimed to evaluate the treatment outcome and toxicity of EPOCH regimen for ENKL.

From June 2003 to June 2008, 34 patients including 30 nasal ENKL (88.2%) and 4 extranasal ENKL (11.8%) received doxorubicin, vincristine, etoposide over 96 hours infusion with bolus cyclophosphamide and oral predinisone (EPOCH) combination as first-line treatment. By the Ann Arbor lymphoma Staging Classification, 29 patients (85.3%) had stage ±E-IIE disease and 5 patients (14.7%) had stage IIIE-‡WE disease. Median cycles of EPOCH regimen administered were 2.5 (range from 1 to 6 cycles). Additional involved field radiation therapy (IFRT) was administered to patients with localized regional disease after chemotherapy.

Among 34 patients, 33 were eligible for objective response evaluation. The response rate (RR) for the whole group was 60.6% (20/33) with complete remission (CR) rate of 45.5% (15/33). The RR of patients with nasal ENKL was 66.7% (20/30), the CR rate was 50% (15/30). Of the 4 patients with extranasal ENKL, only one achieved stable disease (SD), the other three had progressive disease (PD) during chemotherapy. After a median follow-up of 22 (2–68) months, the estimated overall 3-year overall survival rate (OS) was 52.2%. For patients with nasal ENKL, the estimated median survival time was not reached, the 3-year OS was 59.4%. For patients with extranasal ENKL, the estimated median survival time was only 7 months. For stage ±E-IIE patients with nasal ENKL who received initial EPOCH chemotherapy followed IFRT, the CR rate was 75.0%, and the 3-year survival rate was 75.0%. 102 cycles of chemotherapy were administered to 34 patients. Major adverse effect was myelosuppression. The incidence of grade III-‡W neutropenia was 30.9% and 60 cycles needed G-CSF support. Other toxicities were mild, no treatment-related mortality occurred.

EPOCH regiment was effective on ENKL with acceptable toxlicity. EPOCH followed by IFRT yielded promising outcome for patients with localized nasal ENKL. However, patients with extranasal ENKL responded poorly, and more efficacious treatment strategies are urgently needed.

No relevant conflicts of interest to declare.