Adult Soft Tissue Sarcoma Treatment (PDQ®): Treatment - Health Professional Information [NCI] - Treatment Option Overview
To limit acute toxicity with preRX, smaller fields and lower doses are generally given than is the case with PORT. PreRX has been directly compared with PORT for extremity soft tissue sarcomas in a multicenter randomized trial.[13,14,15] Designed to include 266 patients, the trial was stopped early after 190 patients had been accrued because of an increase in wound complications in the preRX group. The scheduled radiation in the preRX group was a wide field of 50 Gy in 2 Gy fractions (first phase of the trial) with an additional 16 Gy to 20 Gy to the tumor bed and a 2-cm margin (second phase of the trial) only if tumor cells were found at the surgical margins.
Patients in the PORT group were scheduled to receive radiation during both phases of the trial. The wound-complication rates were 35% versus 17% in the preRX and PORT groups, respectively (P = .01). In addition, limb function at 6 weeks after surgery was worse in the preRX group (P = .01). At 5 years, the two groups had similar local control rates (93% vs. 92%) and OS (73% vs. 67%, P = .48). Of the 129 patients evaluated for limb function at 21 to 27 months after surgery (n = 73 for preRX and n = 56 for PORT), limb function was similar in both groups, but there was a statistical trend for less fibrosis in the preRX group (P = .07).
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).