Efficacy and safety of hypofractionated preoperative radiotherapy in treatment of patient with primary locally advanced soft tissue sarcoma of limbs/trunk wall.

Abstract

11555 Background: Soft tissue sarcomas (STS) are rare often malignant tumors. The primary treatment of most STS is radical resection with adjuvant radiotherapy. Our previous study showed that the use of preoperative hypofractionated radiotherapy is safe and efficient in the treatment of unselected group of patients with STS. Aim of this study was to assess the use of the treatment scheme in patients with primary STS treated in one institution. Methods: 311 patients (52% female) with primary locally advanced STS participated in this prospective trial conducted from 2010 till 2017. Median age was 55 years (range: 17-91). Median follow up is 57 months (95%CI 55-61). The most common subtypes were pleomorphic sarcoma, liposarcoma and synovial sarcoma. Median tumor size was 11cm. 258 patients (83%) had high grade tumors. The most common tumor localization were lower limbs (72%). 30% of patients received preoperative chemotherapy. For five consecutive days radiotherapy in 5 x 5Gy fraction was applied, with immediate (2-4 days) resection of the tumor. Results: In 260 patients (83.6%) clear surgical margins (R0) were obtained. 107 patients were dead at the time of the analysis.5-year overall survival is 63%. 156 (50%) had a recurrence of the disease. Local recurrence (LR) was found in 13.8% of the patients. Median time from surgery to LR was 14.7 months. In 56% of patients with LR another limb spearing radical surgery could be performed. Factors that had a significant adverse impact on LR were histological subtype (p = 0.017) and surgical margin status (p = 0.013). Factors that had a significant adverse impact on overall survival were tumor size (p < 0.0001), grade (p = 0.0047) and surgical margin status (p = 0.013). 96 patients (30.8%) had any kind of treatment toxicity, factor having negative impact on the toxicity was lower limb location of the tumor (p = 0.0012). 20 patients (6.4%) required surgery for treatment of the complications. 14.6% patients had prolonged healing of the wound ( > 1 month), 8.3% had wound dehiscence, 1.4% required prolonged punctures of the lymph fluid, 2.3% had severe fibrosis leading to contracture of limb, 11% patients prolonged edema of the operated limb. 0.9% of patients had a fracture of the treated limb. Conclusions: In this group, with a big percentage of patients with large, high grade STS use of hypofractionated preoperative radiotherapy was associated with similar local control when compared to published studies. The early toxicity is tolerable, with a small amount of late complications.