Purpose: To develop a novel technique, intraoperative high-dose rate brachytherapy (IOHDR), in the treatment of previously irradiated head and neck cancers located at anatomical sites inaccessible to intraoperative electron beam radiotherapy (IOERT).
Methods: Between October 1992 and June 1997, seven patients (median age = 65 yrs; range = 52 to 71 years) with previously irradiated head and neck recurrences at anatomical sites inaccessible to IOERT in the base of skull were treated with IOHDR after maximal resection for microscopic residual disease. Treatment volume ranged from 6 cc to 24 cc. Six patients received 15 Gy of IOHDR at 0.5 cm; one received 10 Gy using custom-made surface foam applicators.
Results: The median follow-up was 59 months (range 33 to 67 months). It was technically feasible to deliver IOHDR in all seven patients at sites that were inaccessible to IOERT. The morbidity (observed in two patients) was acceptable and generally surgically related. Four of seven patients (57%) were locally controlled at IOHDR site. Two failed regionally, outside the IOHDR treated sites. The disease-free survival ranged from 3 to 30 months (median 9 months) with two patients still alive, disease-free at 28 and 30 months.
Conclusions: IOHDR can be used, with limited toxicity, to treat previously irradiated head and neck cancers at sites inaccessible to IOERT. We are currently evaluating the addition of limited EBRT dose to improve the local control of these poor prognosis recurrent tumors.