Radiotherapy as primary treatment for stage IE and IIE nasal natural Killer/T-cell lymphoma

Purpose The optimal therapy remains unclear for nasal natural killer (NK)/T-cell lymphoma. The purpose of this study is to analyze the outcome of radiotherapy as the primary treatment for localized stage IE and IIE diseases. Patients and Methods One hundred five patient cases were reviewed. There were 83 stage IE and 22 stage IIE patients. All except three patients received radiotherapy (RT) alone or RT combined with chemotherapy (CT; combined-modality therapy [CMTI). Overall, 31 patients were treated with RT alone, 34 with RT followed by CT, 37 with CT followed by RT, and three with CT alone. Results Five-year overall survival (OS) and progression-free survival (PFS) for all patients were 71% and 59%, respectively. The 5-year OS and PFS were 78% and 63% for stage IE, and 46% and 40% for stage IIE, respectively. Complete response (CR) was achieved in 91 patients (87%) after RT and/or CT. Initial RT resulted in a superior CR as compared with initial CT, with 54 (83%) of 65 patients achieving CR with initial RT, versus only eight (20%) of 40 after initial CT. For 102 patients who received RT with or without CT, the outcome of primary treatment with RT alone was compared with that of CMT. Five-year OS and PFS was 66% and 61% for RT alone, and 76% and 61% % for CMT, respectively (OS, P =.6433; PFS, P =.8391). Conclusion RT as primary therapy resulted in good outcome in early-stage disease, and the addition of CT to RT was not accompanied by an improvement in survival.