Combined therapy in untreated patients improves outcome in nasal NK/T lymphoma: results of a clinical trial.

Nasal NK/T-cell lymphoma is a rare presentation of T-cell lymphoma in USA and in Europe, but is the most common presentation in Latin America. The lymphoma is associated with a worse prognosis even in the early stage. Until now, a better treatment has not been determined. We performed a prospective, open-label, controlled clinical trial to assess the efficacy and toxicity of the most common treatment options. We treated 427 patients, of whom 109 patients received radiotherapy (RT), 116 patients received chemotherapy (C), and 202 patients received combined therapy (CT), which were balanced according to stage and prognostic factors. Complete response was achieved in 91 % (95 % confidence interval CI 88-102 %) in CT arm 69 % (95 % CI 61-75 %) in RT arm; and 59 % (95 % CI 48-64 %) in C arm (p < 0.01). A progression-free disease was 91 % (95 % CI 83-96 %); 78 % (95 % CI 69-86 %); and 40 % (95 % CI 32-46 %), respectively (p < 0.01). Actuarial curves of overall survival at 5 years were as follows: 86 % (95 % CI 81-90 %), for CT; 64 % (95 % CI 59-70 %) for RT; and 45 % (95 % CI 39-51 %) for C (p < 0.001). Toxicity was mild and well tolerated. To our knowledge, this is the first controlled clinical trial, with a large number of patients and longer follow-up. Thus, we conclude that CT is the best therapeutic option in this setting of patients.