To evaluate the outcome of CHOP chemotherapy and radiotherapy in Stage IE and IIE nasal natural killer (NK)/T-cell lymphoma, 53 patients with stage IE and IIE nasal NK/T-cell lymphoma were studied. By the Ann Arbor Lymphoma Staging Classification, 41 patients (77%) had Stage IE disease and 12 patients (23%) had Stage IIE disease. All patients were treated curatively using chemotherapy, followed by radiotherapy. Chemotherapy consisted of up to six cycles of the standard CHOP based regimen. The median radiation dose to the tumor bed was 45 Gy for all patients. The median follow-up for all 39 surviving patients was 30.2 months (range, 6 - 104 months). Twenty-six patients had complete response after chemotherapy, and all patients who completed first line chemotherapy achieved complete response after radiotherapy. The 2-year overall survival and progression-free survival rates were 75.6% and 61.8%, respectively. Multivariate analysis revealed that perforation as a presenting symptom, elevated pretreatment serum lactate dehydrogenase level, and ECOG performance status >or=2 were significant independent prognostic factors for this group of patients. Combined chemotherapy followed by involved field radiation produced suboptimal outcome for patients with early stage nasal NK/T-cell lymphoma. Further investigations, preferably prospective clinical trials, for more efficacious treatment strategies are needed to improve the treatment outcome of this malignancy.