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Preliminary results of radiation therapy for locally advanced or recurrent adenoid cystic carcinomas of the head and neck using combined conventional radiation therapy and hypofractionated inverse planned stereotactic radiation therapy.

PURPOSE
To investigate the clinical outcomes and feasibility of combined conventional radiation therapy (RT) and hypofractionated inverse planned stereotactic radiation therapy (SRT) for locally advanced or recurrent adenoid cystic carcinomas (ACCs) of the head and neck.


PATIENTS AND METHODS
Five patients with ACCs of the head and neck were treated with combined conventional RT and inverse planned SRT. Radiation doses of 40 to 50 Gy were delivered with 20 to 25 fractions using conventional RT, and then an additional 20 to 25 Gy was delivered by 4 to 5 fractions of SRT.


RESULTS
Median follow-up was 12 months. Local control was obtained in all 5 patients, PR in 2 patients and SD in 3 patients. According to the Radiation Therapy Oncology Group (RTOG) late-radiation morbidity scoring criteria, adverse effects included Grade 2 xerostomia in 1 patient, Grade 2 trismus in 1 patient, and Grade 4 mucosal ulceration in 1 patient.


CONCLUSION
Combined treatment with conventional RT and hypofractionated inverse planned SRT may be effective for short-term local control in patients with locally advanced or recurrent ACCs. Further evaluation is needed for long-term follow-up.