Interstitial radiation therapy in the treatment of childhood soft-tissue sarcomas.

Between 1971 and 1985, 12 children and adolescents aged 0.7 to 19 years (median 4.7 years) with localized residual soft-tissue sarcomas (STS) underwent interstitial radiation therapy (IRT) at our institution. Eight received IRT as a component of initial therapy, and four were treated for recurrent or persistent disease. Tumor sites were head and neck (6), pelvis (4), extremity (1), and retroperitoneum (1). The radionuclides employed were Iridium-192 (9), Iodine-125 (2), and Californium-252 (1). The median prescribed dose in the Iridium-192 group was 3960 cGy (1955-7300). Seven of eight children receiving IRT during initial therapy have maintained local control, and six remain without evidence of disease for a median follow-up time of 5.8 years (2.0-16.0). One of the four patients treated for recurrent disease is free of disease after salvage surgery, and the other three are dead of disease. Multidisciplinary evaluation of the nine patients with more than 2 years of follow-up revealed functional and cosmetic effects of IRT to be minimal. IRT can be an effective method of delivering high dose irradiation in childhood sarcomas while reducing the deleterious effects in adjacent normal tissues.