Objective:To analyze the treatment results of primary nasopharyngeal carcinoma (NPC) treated in our institution in the beginning of the 21st century to identify key failures and late effects for refining future treatments.Methods:1093 patients with primary NPC treated during December 2001 and June 2003 were retrospectively analyzed.The distribution according to the AJCC/UICC (2002 edition) staging system was stage Ⅰ in 5.8%,stage Ⅱ 40.2%,stage Ⅲ 32.7% and stage Ⅳa-b 21.3%.Four different ERT techniques were used:fluoroscopy simulation conventionaI radiotherapy (CR) in 74.3% of patients,computer tomography simulation conventional radiotherapy (CT-sim CR) 14.2%,three-dimensional conformal radiotherapy (3D-CRT) 6.3%,intensity modulated radiotherapy (IMRT) 5.2%.In the whole series,46.7% of patients had additional treatment with chemotherapy.Results:The 4-year local failure-free rate (LFFR),nodal failure-free rate,distanl metastasis-free rate,progression-free survival and overall survivaI (OS) was 89.6%,96.1%,85.9%,73.0% and 82.4%.respectively.The stage was the most important prognostic factor.The 4-year OS and LFFR of patients treated by CR,CT-sim CR,3D-CRT and IMRT was 80.2%,89.8%,89.8%,92.4% and 87.7%,96.4%,91.0%,96.5%,respectively.The morbidity and degree of xerostomia and trismus were lower in the patients treated by 3D-CRT and IMRT than by CR and CT-sim CR.Conclusion:Treatment results of primary NPC in our institution have been substantially improved.Distant metastasis is the main failure.The CT simulation and conformal radiotherapy can enhance the OS and LFFR,and conformal radiotherapy can reduce the morbidity and degree of late effects.