Pilot study of pegylated interferon alpha-2a treatment during chemo- and radiotherapy and post-remission maintenance in patients with EBV-positive extranodal NK/T cell lymphoma

The role of the Epstein–Barr virus (EBV) in the pathogenesis of extranodal natural killer/T-cell lymphoma (ENKTCL), and its resistance to chemotherapy raises the possibility of antiviral therapeutic strategies. The aim of this prospective pilot study was to evaluate the feasibility and effectiveness of antiviral treatment using pegylated interferon alpha-2a (pIFN α-2a) as an adjunct to induction and maintenance therapy in patients with ENKTCL. A total of seven patients with newly diagnosed EBV-positive ENKTCL were enrolled. Pegylated IFN α-2a was administered during induction chemoradiotherapy. If patients achieved a partial or complete response (PR or CR, respectively), high-dose chemotherapy with autologous stem cell transplantation (HDT/SCT) was given. After transplantation, maintenance therapy included pIFN α-2a for 3 years. Of the patients available for evaluation, all achieved a CR or PR after induction therapy but one patient relapsed before HDT/SCT. The event free survival and overall survival at 3 years were 50.0 ± 20.4% and 66.7 ± 19.2%, respectively. The 3-year disease-free survival after transplantation of the patients that received maintenance therapy was 80.0 ± 17.9%. The results of this pilot study indicated that pIFN α-2a containing induction and maintenance therapy was feasible and effective for ENKTCL.