Treatment of oral cavity and oropharyngeal cancer. Indications, technical aspects, and results of interstitial brachytherapy.

Excellent local control rates of interstitial brachytherapy in oral cavity cancer and oropharyngeal carcinoma have been demonstrated in different retrospective studies. Compared to external-beam radiation therapy the high local control rates with a low rate of side effects obtained by interstitial brachytherapy are the result of a steep dose reduction in the implant-surrounding normal tissues. Therefore, interstitial brachytherapy offers rather the possibility to give high doses without inevitably leading to high complication rates. Low-dose-rate (LDR) and pulsed-dose-rate (PDR) interstitial brachytherapy with 0.4-0.55 Gy/h/24 h for tumors of the oral cavity and oropharynx in selected patients is a proven, effective and safe treatment method with excellent long-term data both as a sole treatment modality and a postoperative method, as well as a unique treatment method of head and neck tumors in previously irradiated areas. This paper deals with the technical aspects of interstitial brachytherapy, that seem to be relevant to high-quality outcome, and gives an overview of indications as well as past and recent results of interstitial brachytherapy in head and neck cancer.