Preoperative vs. postoperative radiation therapy for soft tissue sarcoma: A retrospective comparative evaluation of disease outcome

Purpose: Radiation (XRT) is a proven component in the treatment of soft tissue sarcoma. However, there is little evidence regarding the relative effectiveness of preoperative vs. postoperative XRT. This retrospective study addresses the relative effectiveness of disease control by these two treatment sequences. Methods and Materials: A total of 517 patients (246 treated with postoperative XRT, and 271 treated with preoperative XRT) with nonmetastatic sarcoma were evaluated for disease outcome and late complications using univariate and multivariate techniques. Results: With a median follow-up of 6 years, overall local control was 81% and 78% at 5 and 10 years, respectively. Although local control appeared superior with preoperative XRT (83% at 10 years) compared with postoperative XRT (72%), multivariate analysis revealed that this difference could be entirely explained by the unequal distribution of prognostic factors between the two groups, and there was no evidence that treatment sequence independently determined local control. There were no differences in nodal or metastatic relapse between the two treatments, and disease-specific survival was not significantly different. There was a slightly higher incidence of late XRT-related complications among those treated with postoperative XRT (10-year incidence of 9% vs. 5%, p = 0.03). Conclusions: This study found no evidence for differences in disease outcome attributable to the use of either pre- or postoperative XRT. There was a slight increase in long-term complications with postoperative XRT, likely due to the higher doses used in this sequence.