Abstract A series of 131 patients with carcinoma of the nasopharynx were seen at the University of Chicago between 1949 and 1977. Within this series a subset of 96 patients received initial radiation treatment with curative intent at our institution, and comprises the basis of this report. Treatment doses to both the primary tumor site and the cervical spinal cord were converted to nominal standard doses (NSD). The patients were categorized into NSD intervals from 1200 to greater than 2 100 ret with corresponding incidence of complication: radiation induced cervical cord myelitis and recurrence at the primary site. Paired dose-response curves are presented that show tumor ablation and cervical myelitis as a complication of treatment versus NSD. The 5 % and 10 % incidence levels of radiation induced cervical myelitis are 1450 and 1750 ret, respectively. The therapeutic operating characteristic (TOC) curve of probability of tumor ablation versus the probability of cervical myelitis is developed and shown. A 10 % complication rate resulted from tumor control rates of 53% and 33% for T1, T2 and T3, T4 primary lesions, respectively. An additional 5% increase in cervical myelitis resulted from a 15 % gain in tumor ablation within all levels of primary tumor extension. Because of the higher tolerance of the cervical spinal cord and the poor prognosis for those patients who developed a recurrence at the primary site, the more aggressive treatment approach to all stages of nasopharyngeal carcinoma is proposed.