Brachytherapy has also been investigated as an adjuvant therapy for soft tissue sarcomas. Although it has possible advantages of convenience and less radiation to normal surrounding tissue relative to EBRT, the two treatment strategies have not been directly compared in terms of efficacy or morbidity. However, adjuvant brachytherapy has been compared to surgery without radiation.
In a single-institution trial, 164 patients with sarcomas of the extremity or superficial trunk were randomly assigned during surgery, if all gross tumor could be excised, to receive an iridium-192 implant (delivering 42 Gy-45 Gy over 4-6 days; 78 patients) or to a control arm of no radiation (86 patients).[16,17] Some of the patients with high-grade tumors received adjuvant doxorubicin-based chemotherapy if they were thought to be at a high risk for metastasis (34 patients in each study arm). With a median follow-up of 76 months, the 5-year actuarial local recurrence rates were 18% and 31% in the brachytherapy and control arms, respectively (P = .04). This difference was limited to patients with high-grade tumors. There was no discernible difference in sarcoma-specific survival rates between the brachytherapy and control arms (84% and 81%, respectively; P = .65), and there was no difference in the high tumor-grade group.[Level of evidence: 1iiDiii] The rates of clinically important wound complications (e.g., need for operative revision or repeated seroma drainage, wound separation, large hematomas, or purulent infection) were 24% and 14% in the radiation and control arms, respectively (P = .13); wound reoperation rates were 10% and 0%, respectively (P = .006).
Intensity-modulated radiation therapy (IMRT) has been used to deliver preRX or PORT to patients with extremity soft tissue sarcomas in an effort to spare the femur, joints, and selected other normal tissues from the full prescription dose and to maintain local control while potentially reducing radiation therapy-related morbidity. Initial single-institution reports suggest that high rates of local control with some reduction in morbidity are possible with this technique.[18,19]
In some tumors of the extremities or trunk, surgery alone can be performed without the use of radiation. Evidence for this approach is limited to single-institution, relatively small, case series [1,20,21] or analysis of outcomes in the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) tumor registry. However, these comparisons suffer from low statistical power and differential evaluability rates that could have introduced bias. Patient selection factors may vary among surgeons. In general, this approach is considered in patients with low-grade tumors of the extremity or superficial trunk that are less than or equal to 5 cm in diameter (T1) and have microscopically negative surgical margins; long-term local tumor control is about 90% in such patients.