ESTRO 2021 Abstract Book

S1173

ESTRO 2021

Conclusion The outcome of the scalp angiosarcoma patients treated with IMRT in our institution was favorable with acceptable toxicity.

PO-1428 Adjuvant Radiotherapy on Skin Grafts After Limb-Sparing Surgery in the Treatment of Sarcomas S. Gonçalves 1 , L. Rolim 1 , J. Casalta-Lopes 2 , A. Silva 3 , M. Jacobetty 1 , J. Freitas 4 , R. Fonseca 4 , J. Rodrigues 4 , P. F. Tavares 4 , J. M. Casanova 4 , M. Borrego 1 1 Centro Hospitalar e Universitário de Coimbra, Radiation Oncology, Coimbra, Portugal; 2 Centro Hospitalar e Universitário de Coimbra, Radiotherapy, Coimbra, Portugal; 3 Centro Hospitalar e Universitário de Coimbra, Radiation Oncology; Bone and Soft Tissue Tumor Unit, Coimbra, Portugal; 4 Centro Hospitalar e Universitário de Coimbra, Bone and Soft Tissue Tumor Unit, Coimbra, Portugal Purpose or Objective Limb-sparing surgery is the standard approach in the treatment of sarcoma of the extremities, sometimes only possible with the use of skin grafts to repair the tissue defects. The most common side effect after limb- sparing surgery and adjuvant radiotherapy is wound complications, but there are few data on the tolerance of skin grafts to adjuvant radiation. This study aims to evaluate tolerance of skin grafts to radiotherapy and possible contributor factors. Materials and Methods Retrospective analysis of patients with skin grafts treated with adjuvant radiotherapy between 2002-2019 in a radiotherapy department. Results A total of 15 patients was evaluated, with median age of 52years; Karnofsky ≥90% in 60%. Patient comorbidities was hypertension in 40%; diabetes in 13.3% and smoking habits in 33.3%. About the tumor, 73.3% were in lower extremity; 73.3% staged as cT1-2; median size of 5cm; 60% were deep; the most frequent histology was liposarcoma (20%). Of all the patients, 40% received neoadjuvant Chemotherapy; 6.7% adjuvant, and 6.7% concomitant with radiotherapy. Skin grafts were used in the primary surgery in 33.3% of the patients, 46.7% in recurrence’s excision, 20% due to previous complications; 60% had radical resection and 20% debridement; the surgery was R1 in 73.3%; free grafts were used in 66.7%. Surgical complications were present in 33.4%, with wound dehiscence (13.3%); graft necrosis (6.7%); infection (6.7%); and hematoma (6.7%); 13.3% needed posterior debridement surgery with graft. Median time surgery-radiotherapy was 83 days; radiotherapy dose was 66Gy/33fr in 33.3% and 60Gy/30fr in 33.3%; one patient interrupted treatment at 45Gy. No bolus were used, all treatments were 3D-CRT. During the treatment, all patients presented radiodermatitis, 13.3% dry and 26.7% moist desquamation; 6.7% graft dehiscence; 40% edema. About late toxicity, 6.7% lost the graft, 40% presented fibrosis, 6.7% radiation ulcer. One patient underwent 6 surgeries after the radiotherapy due to graft complications. It was verified that a longer surgery-radiotherapy time was significantly related to fewer acute complications (p=0.026), but was not related with late toxicity. No significant relation between chemotherapy, surgical complications, graft origin, radiation dose, tumor size, patient comorbidities and acute or late toxicity was observed. Conclusion There were no unexpected complications of radiotherapy. A longer surgery-radiotherapy time was significantly associated with fewer acute complications, and this should be considered when determining the radiotherapy timing after the surgery. PO-1429 Long term results of neoadjuvant radiotherapy in soft tissue sarcomas of the extremities A. CortesI 1 , E. Galietta 2,3 , M.L. Alfieri 2,3 , M. Buwenge 2,3 , C.M. Donati 2,3 , S. Bisello 2,3 , M. Boriani 2 , G. Ghigi 1 , A. Romeo 1 , G. Bianchi 4 , M. Gambarotti 5 , A. Righi 5 , G. Macchia 6 , F. Deodato 6 , S. Cilla 7 , B. Rombi 8 , A.G. Morganti 2,3 , S. Cammelli 2,3 1 Radiotherapy Unit, IRCCS Istituto Romagnolo per lo Studio dei Tumori (IRST) "Dino Amadori", Meldola, Italy; 2 Radiation Oncology, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy; 3 Department of Experimental, Diagnostic, and Specialty Medicine - DIMES, Alma Mater Studiorum Bologna University, Bologna, Italy; 4 Department of Orthopedic Oncology, Istituto Ortopedico Rizzoli, Bologna, Italy; 5 Department of Pathology, Istituto Ortopedico Rizzoli, Bologna, Italy; 6 Radiation Oncology Unit, Gemelli Molise Hospital –