Stereotactic radiosurgical boost following radiotherapy in primary nasopharyngeal carcinoma: Impact on local control

Purpose: Treatment of patients with nasopharyngeal carcinoma using external beam radiation therapy (EBRT) alone results in significant local recurrenc e. Although intracavitary brachytherapy can be used as a component of manag ement, it may be inadequate if there is extension of disease to the skull b ase. To improve local control, stereotactic radiosurgery was used to boost the primary tumor site following fractionated radiotherapy in patients with nasopharyngeal carcinoma. Methods and Materials: Twenty-three consecutive patients were treated with radiosurgery following radiotherapy for nasopharyngeal carcinoma from 10/92 to 5/98. All patients had biopsy confirmation of disease prior to radiatio n therapy; Stage III disease (1 patient), Stage IV disease (22 patients), F ifteen patients received cisplatinum-based chemotherapy in addition to radi otherapy. Radiosurgery was delivered using a frame-based LINAC as a boost ( range 7 to 15 Gy, median 12 Gy) following fractionated radiation therapy (r ange 64.8 to 70 Gy, median 66 Gy). Results: All 23 patients (100%) receiving radiosurgery as a boost following fractionated radiation therapy are locally controlled at a mean follow-up of 21 months (range 2 to 64 months). There have been no complications of tr eatment caused by radiosurgery. However, eight patients (35%) have subseque ntly developed regional or distant metastases. Conclusions: Stereotactic radiosurgical boost following fractionated EBRT p rovides excellent local control in advanced stage nasopharynx cancer and sh ould be considered for all patients with this disease. The treatment is saf e and effective and may be combined with cisplatinum-based chemotherapy. (C ) 1999 Elsevier Science Inc.