Interstitial brachytherapy for childhood soft tissue sarcoma.

Background: To evaluate the efficacy of interstitial brachytherapy (BRT) in children undergoing combined modality treatment for soft tissue sarcomas (STS).

Procedure: From September 1984 to December 2003, 50 children (median age 13 years, range 1 to 18) with STS who received BRT as part of loco-regional treatment were included. There were 30 males and 20 females, the majority (68%) had primary lesions, synovial sarcoma (32%) was the most common histological type, and 26% had high-grade lesions. Treatment included wide local excision and BRT with or without external beam radiotherapy (EBRT). Thirty children (60%) received BRT alone.

Results: After a median follow-up of 51 months, the local control (LC), disease-free survival, and overall survival were 82%, 68%, and 71%, respectively. LC was superior in patients with tumor size 5 cm (96% vs. 67%, P = 0.04), symptom duration <2 months versus >2 months (100% vs. 73%, P = 0.05), and Grade I versus Grade II versus Grade III tumors (100% vs. 93% vs. 57%, P = 0.03). Children receiving a combination of BRT and EBRT had comparable LC to those receiving BRT alone (78% vs. 84%, P = 0.89). There was no significant difference in LC for patients receiving LDR versus HDR BRT (77% vs. 92%, P = 0.32, for BRT alone; and 67% vs. 100%, P = 0.17, for BRT + EBRT).

Conclusion: Interstitial BRT with or without EBRT appears to result in satisfactory outcome in children with STS. Radical BRT alone, when used judiciously in select groups of children, results in excellent local control and functional outcome with reduced treatment-related morbidity.