Radiation Therapy for Squamous Cell Carcinoma of the Tonsil

To characterize the patient population referred for radiation therapy for tonsillar cancer and to assess the effectiveness of use only radiation therapy in this population. We retrospectively reviewed the medical records of 21 patients referred to the Mayo Clinic in Rochester, Minnesota, from 1970 through 1988 for radiation therapy for squamous cell carcinoma of the tonsillar region. The median age of the 21 study patients was 65 years (range, 45 to 92), and the male:female ratio was 12:9. In all patients, follow-up continued until death or for 2.25 to 16.25 years. Of the 21 patients, 17 had tumors that were either surgically unresectable or medically inoperable, and 20 had clinical stage III or IV disease. The median total dose of irradiation was 55 Gy. Local control of the tonsillar cancer was as follows: T2, four of five patients; T3, seven of seven; and T4, five of nine. Thus, the local control rate was 76%. No associations were discovered among local control, total dose of radiation therapy, dose per fraction, overall duration of treatment, age, sex, or reason for referral for radiation therapy. Control of metastatic cervical adenopathy was as follows: clinical stage N1, seven of seven patients; N2, six of seven; and N3, one of one. (Six study patients had no nodal involvement.) The estimated 5-year cause-specific survival and overall survival rates were 77% and 31%, respectively. This study substantiates the effectiveness of radiation therapy in patients with squamous cell carcinoma of the tonsil.