[Application of CyberKnife stereotactic radiosurgery in the treatment of head and neck cancer].

The treatment of squamous cell carcinoma of the head and neck is multimodal, including surgery, chemotherapy, and radiotherapy, or the combination of those. Though aggressive treatment results in complete tumor remission in many patients even in locally advanced stages, unfortunately local relapse is not uncommon. For patients not candidate for salvage surgery, chemotherapy and conventional fractionated external beam irradiation can be applied. However, for patients previously treated with full-dose radiotherapy, the deliverable reirradiation dose is limited, considering the elevated risk of toxicity caused by cumulative doses. CyberKnife is a highly conformal radiosurgical technology which can successfully treat this subset of patients. In addition, it can be applied for hardly resectable rare tumors of the skull base and the head and neck region like chordoma, chondrosarcoma and paragangliomas. The CyberKnife stereotacic radiosurgery technology is now available in Hungary, in the National Institute of Oncology.