Intraoperative electron irradiation in the management of pediatric malignancies

External beam irradiation (PBRT), especially in children, is limited by the radiosensitivity of normal tissues. Local control remains a problem in abdominopelvic childhood malignancies. Intraoperative electron irradiation (IOERT) has the potential to increase the dose to the tumor, thereby improving local control, without increasing treatment morbidity.

Between February 1983 and October 1990, 11 children received IOERT as part of a multidisciplinary treatment program for locally advanced primary or recurrent abdominopelvic malignancies. The 7 boys and 4 girls ranged in age from 2-18 years. Tumor histologies included four neuroblastomas, two desmoid tumors, and one each of the following: embryonal rhabdomyosarcoma, synovial cell sarcoma, neurofibrosarcoma, malignant fibrous histiocytoma, and paraganglioma. Single radiation doses of 10-25 grays were delivered using 6-15-megaelectron volt electron beams to 1-5 IOERT fields. All patients also underwent EBRT and six received chemotherapy.

Eight patients (73%) were alive and disease free at a median follow-up of 99 months (range, 37-126 months). All eight patients who underwent gross total resection were locally controlled. Three patients required surgical intervention for IOERT-related complications and two patients developed neuropathies.

IOERT as part of a multidisciplinary treatment approach in patients with locally advanced pediatric malignancies appears to enhance local control in those patients in whom a gross total resection is possible. The long term survival rate was encouraging. Further study, with a larger number of patients, appears warranted to more carefully delineate the efficacy and tolerance of IOERT in the pediatric population.