Is radiation therapy a preferred alternative to surgery for squamous cell carcinoma of the base of tongue?

Purpose: To evaluate irradiation alone for treatment of base-of-tongue cancer. Patients and Methods: Two hundred seventeen patients with squamous cell carcinoma of the base of tongue were treated with radiation alone and had follow-up for greater than or equal to 2 years. Results: Local control rates at 5 years were as follows: T1, 96%; T2, 91%; T3, 81%; and T4, 38%. Multivariate analysis revealed that T stage (P = .0001) and overall treatment time (P = .0006) significantly influenced local control. The 5-year rates of local-regional control were as follows: I, 100%; II, 100%; III, 83%; IVA, 64%; and IVB, 65%. Multivariate analysis revealed that the following parameters significantly affect the probability of this end point: T stage (P = .0001), overall treatment time (P = .0001), overall stage (P = .0131), and addition of a neck dissection (P = .0021). The rates of absolute and cause-specific survival at 5 years were as follows: I, 50% and 100%; II, 81% and 100%; III, 65% and 76%; IVA, 42% and 56%; and IVB, 44% and 52%. Severe radiation complications developed in eight patients (4%). Conclusion: The likelihood of cure after external-beam irradiation wets related to stage, overall treatment time, and addition of a planned neck dissection. The local-regional control rates and survival rates alter radiation therapy were comparable to those after surgery, and the morbidity associated with irradiation was less. (C) 2000 by American Society of Clinical Oncology.