Preliminary results from a prospective study using limited margin radiotherapy in pediatric and young adult patients with high-grade nonrhabdomyosarcoma soft-tissue sarcoma.

PURPOSE: To demonstrate the safety and efficacy of limited margin radiotherapy in the local control of pediatric and young adult patients with high-grade nonrhabdomyosarcoma soft tissue sarcoma (NRSTS).

METHODS AND MATERIALS: Pediatric patients with high-grade NRSTS requiring radiation were treated on an institutional review board approved prospective institutional study of conformal/intensity-modulated/interstitial brachytherapy using a 2-cm anatomically constrained margin.

RESULTS: A total of 32 patients (median age, 15.3 years; range, 2-22 years) received adjuvant (27 patients) or definitive (5 patients) irradiation. With a median follow-up of 32 months, the 3-year cumulative incidence of local failure was 3.7% for patients undergoing irradiation after surgical resection. Four patients experienced local failure; the mean dose to the volume of recurrence was >or=97% of the prescribed dose.

CONCLUSIONS: Delivery of limited margin radiotherapy using external beam or brachytherapy provides a high rate of local tumor control without marginal failure. Further follow-up is required to determine whether normal tissue effects are minimized using this approach.