Mediastinal Preventive Radiotherapy in the Patients with N3 Cervical Lymph Node Metastasis of Nasopharyngeal Carclnoma

From January 1991 to February 1992, 41 patients with N3 cervical lymph node metastasis of nasopharyngeal carcinoma were treated.The patients were randomized into mediastinal preventive radiation(prevention group)(21 patients)and coventionl radiation(contral group)(20 patients).Mediastinal preventive radiation treatment was 50Gy/5wk.At 1. 5 to 2 year's followup survey,the rate of distance metastasis in two groups were 28. 6% (6/12) and 45%(9/20)(P0.05).There was no statistical significance in the differences between these two groups.