Journal of Clinical Oncology, Vol 15, 3075-3084, Copyright © 1997 by American Society of Clinical Oncology
Innovation in the management of soft tissue sarcomas in infants and young children: high-dose-rate brachytherapy
S Nag, R Martinez-Monge, F Ruymann, A Jamil and C Bauer
Arthur G. James Cancer Hospital and Research Institute, Columbus, OH, USA. nag.1@osu.edu
PURPOSE: Conventional low-dose-rate (LDR) brachytherapy is effective in
treating childhood sarcomas, but often not practical (due to the associated
radiation hazards) in the young children who require continuous observation
and sedation. Fractionated high-dose-rate brachytherapy (HDR) was used to
deliver adequate tumoricidal radiation while preserving bone and organ
growth in children. MATERIALS AND METHODS: Twelve children with diverse
sarcomas were treated with fractionated HDR. The median age at diagnosis
was 18 months (range, 1 to 42). Nine patients had rhabdomyosarcoma and
three had other soft tissue sarcoma (STS) variants. Ten patients had
microscopic residual disease at the time of brachytherapy. All patients
were treated with appropriate chemotherapy and surgery. HDR was delivered
in 3-Gy fractions twice a day to a total dose of 36 Gy in 8 days.
External-beam radiation therapy (EBRT) was avoided. Patients were monitored
for a median of 61 months (range, 30 to 78). RESULTS: One patient developed
local recurrence and distant metastases to the lungs. The 6-year actuarial
local control and overall survival rates were 91% and 81%, respectively.
Brachytherapy-related morbidity occurred in 50% of patients. The morbidity
was mild to moderate in 42% of patients and consisted primarily of acute
skin and mucosal reaction. One patient experienced severe (grade III to IV)
toxicity. Another child, treated to the tongue, had delayed dentition only
in the teeth adjacent to the brachytherapy site. The other children have
exhibited only minimal or none of the bone growth retardation expected with
EBRT. CONCLUSION: The combination of conservative surgery, chemotherapy,
and exclusive HDR to postchemotherapy tumor volume with a modest margin,
avoiding EBRT, provided disease control in carefully selected young
children, while preserving bone growth and organ function. The short
duration of therapy and small volume irradiated allowed chemotherapy to be
resumed shortly after brachytherapy. The use of HDR challenges the present
philosophy of radiotherapy treatment volume, which holds that the
prechemotherapy tumor volume should be treated with an acceptable margin.
Brachytherapy should be included in multicentric clinical trials in young
children.
