Paragangliomas of the Head and Neck Treated With External-Beam Radiotherapy

Abstract

To evaluate the results of treatment for 104 patients with 121 paragangliomas of the temporal bone, carotid body, or glomus vagale who were treated with radiation therapy (RT) alone or after subtotal resection at the University of Florida between 1968 and 2004. Eighty-nine (86%) patients were treated with conventional megavoltage techniques, 15 (14%) patients with stereotactic fractionated radiotherapy (SRT), 6 (6%) patients with stereotactic radiosurgery (SRS), and 11 (11%) patients with IMRT. One hundred four lesions were previously untreated, whereas 17 had undergone prior treatment (surgery, 14 lesions; RT, 1 lesion; or both, 2 lesions) and were treated for locally recurrent disease. All 3 patients who received prior RT had been treated at other institutions. Four (4%) patients had metastatic neck disease at presentation. Patients had minimum follow-up times as follows: 2 years, 104 patients (100%); 5 years, 78 patients (75%); 10 years, 42 patients (40%); 15 years, 21 patients (20%); 20 years, 12 patients (11%); 25 years, 5 patients (5%); and 30 years, 4 patients (4%). There were 6 local recurrences at 0.7 years, 1.4 years, 2.6 years, 4.5 years, 5.2 years, and 8.2 years. Five were in glomus jugulare tumors and one was in a carotid body tumor. Two of the six recurrences had been treated previously at other institutions with RT and/or surgery. A third recurrence occurred after a geographic miss with stereotactic radiosurgery (SRS). Treatment for a fourth recurrence was discontinued against medical advice before receiving the prescribed dose. There were, therefore, only 2 failures in 104 previously untreated lesions receiving the prescribed course of RT. One recurrence was successfully salvaged with additional RT. Salvage attempts in 2 other patients were unsuccessful. The actuarial local-control probability and cause-specific survival at 10 years were 94% and 95%, respectively. The overall crude local-control rate for all 121 lesions was 95%, with an ultimate local-control rate of 96%. The incidence of grade 1 and 2 treatment-related complications was low. There were no severe treatment complications. Irradiation offers a high probability of tumor control with relatively minimal risks for patients with chemodectomas of the temporal bone and neck.