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Techniques for radiofrequency ablation of head and neck tumors.

OBJECTIVES
To describe the various techniques that have been developed for application of radiofrequency ablation in the palliative treatment of recurrent and advanced head and neck malignant tumors.


DESIGN
Case series with a follow-up of 3 to 18 months.


SETTING
Faculty practice, research protocol, tertiary care academic medical center.


PATIENTS
Fifteen treatments were administered over a 3-year period to 12 patients with advanced and/or recurrent tumors. Eleven tumors were squamous cell carcinomas of the oral cavity, oropharynx, and maxillary sinus, and 1 tumor was a medullary thyroid carcinoma. Three of the 12 patients were treated on 2 separate occasions. Patients were selected as a referred sample and sent specifically for treatment with radiofrequency ablation because they were not candidates for the standard curative options of radiation or surgery. No patient refused enrollment, nor were any patients withdrawn because of adverse events.


INTERVENTION
Radiofrequency ablation is a method of localized hyperthermia resulting in tissue necrosis. Ninety to 150 W of energy is applied, achieving intratumoral temperatures of 60 to 110 degrees C for 5 to 15 minutes per ablation. Techniques have been developed to apply radiofrequency ablation under direct vision, endoscopically, percutaneously, and with ultrasound and computed tomographic guidance.


RESULTS
The radiofrequency ablation probe was accurately placed and treatment administered on 15 occasions. No perioperative deaths occurred. One patient suffered a stroke. Subjective patient improvement was reported with regard to pain (n=9), appearance (n=3), and function (n=4).