Long-term morbidity in children treated with fractionated high-dose-rate brachytherapy for soft tissue sarcomas

The purpose of this study was to determine the long-term local control, disease-free survival, and morbidity of fractionated high-dose-rate brachytherapy (F-HDR) in infants and children with soft tissue sarcomas.

Fifteen children (13 girls and 2 boys, ages 5-101 months) with soft tissue sarcomas were treated with chemotherapy, organ-preserving surgery, and F-HDR (36 Gy in 12 fractions) to post-chemotherapy volumes. External beam radiotherapy was not part of the primary treatment, although four patients (27%) subsequently received salvage external beam radiotherapy after treatment failure. Chemotherapy was administered to all patients based on their tumor histology and stage.

After a median follow-up of 10 years (range 32-154 months), 12 patients (80%) were alive without evidence of disease. Ten-year overall survival and local control rates were both 80% (12/15 children). The overall survival was better (91%) for children with microscopic residual versus gross residual disease (75%). With longer follow-up, grade 3 to 4 brachytherapy-related late morbidities increased from 8% (1/12) to 20% (3/15) and included trismus/osteonecrosis, vaginal stenosis, and periurethral fibrosis. There were two late complications associated with puberty that occurred 8 to 10 years after the initial treatments. Acute toxicity occurred in five patients (38%) and consisted primarily of grade 1 to 3 skin and mucosal reactions.

As the sole radiation modality, F-HDR achieved excellent local control and disease-free survival in properly selected children with soft tissue sarcomas while preserving normal bone and organ development. A significant percentage of patients experience adverse late sequelae as a result of this treatment.