Carcinoma of the nasopharynx. Eighteen years' experience with megavoltage radiation therapy.

From 1956 through 1973, 82 patients with carcinoma of the nasopharynx received high dose megavoltage radiation therapy at Stanford University. The actuarial disease-free (NED) survival was 62% at 5 years and 56% at 10 years. The NED survivals at 5 years for patients with T1, T2, and T3 lesions were 76%, 68%, and 55%, respectively. No T4 patients were salvaged, but two of 10 patients who presented with cranial nerve dysfunction were long-term survivors. The degree of nodal involvement also had prognostic significance. Involved lymph nodes were successfully controlled in all instances when doses of at least 6500 rads were given. Initial treatment failed in 32 patients. In 24 (75%) this occurred within 18 months. Thirteen patients with initial recurrences in head and neck sites were retreated and three remain alive. Survival after retreatment ranged from 2 months fo 10 years, with a median of 16 months. Although nearly one-third (6/17) of the patients with local recurrences had initial T1 or T2 lesions, there have been no failures in patients treated for these early stages in the last 7 years. This may be attributed to the use of larger treatment fields. Likewise, prophylactic irradiation of the neck was always successful in preventing nodal disease if the primary site was controlled.