Short Course of Radiotherapy Prior to Surgery of Soft Tissue Sarcomas

Based upon the preliminary data derived from first SCOPES clinical trial and the results of patients treated during the recent COVID-19 pandemic, patients with soft tissue sarcomas (STS) can be preoperatively irradiated in a modestly hypofractionated schedule of 14 x 3 Gy. From a toxicity and efficacy point of view, this regimen equals the outcomes after a conventionally fractionated regimen of 25 x 2 Gy in five weeks. Moreover, the rationale for investigating (modest) hypofractionation in the clinic comes both from a logistic point of view (patient convenience and a lower pressure on radiotherapy equipment), form prior phase II clinical evidence and from (cellular) radiobiological observations. There is phase II trial evidence suggesting that even more (ultra-) hypofractionation to 5 x 6 Gy is also safe and effective. Within this study, patients will be randomized to receive either the modestly hypofractionated conventional schedule of 14 x 3 Gy or an even shorter preoperative regimen of 5 x 6 Gy, in the hypothesis that both the postoperative wound complication rate until 120 days after surgery, as well as the local control probability at two years are comparable in both arms.