ESTRO 37 Abstract book

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ESTRO 37

intent, this threshold of 110 ml or less for the PTV revealed a statistically significant difference when comparing local control with disease recurrence (P=0.019, Fisher’s exact test).

treated with curative intent between 2010 and 2015 were retrospectively analysed. Median age was 22 years (range: 10 - 43 years) with majority being extrapelvic primary tumors (n=10; 58%). Size of primary tumor ranged between 5.9 – 17.4 cm. Majority of them had oligo metastatic disease [≤3 bone metastasis = 5 (29.4%); ≤3 marrow metastasis = 4 (23.5%); lung + marrow +/- bone/node = 4 (23.5%); >3 marrow metastasis = 1 (5.9%); lung + bone = 1 (5.9%); node = 1 (5.9%); soft tissue = 1 (5.9%)]. Single and multiple site of metastasis was present in 9 (53%) and 8 (47%) patients respectively. Complete response based on whole body FDG PET CT was present in 5 patients post induction chemotherapy. After local radiation, complete response at primary and metastatic site was seen in 11 (64.7%) and 13 (76.5%) patients respectively. At a median follow up of 28 months (range 5 - 70 months) none of the patients had died due to disease. Two patients (11.8%) had died of chemotherapy-related toxicity. Relapse was seen in 2 out of 11 patients (18.2%) with complete response post local radiation and in 4 out of 5 patients (80%) who did not have complete response. Relapse was seen in 3 out of 9 patients (33.3%) with single site of metastasis and 3 out of 8 patients (37.5%) with multiple site of metastasis. The 3-year Event Free Survival (EFS) and Overall Survival (OS) was 55.5% and 86.9% respectively. Conclusion This study shows that in Ewing sarcoma patients with limited metastatic disease at presentation curative intent treatment with multiagent chemotherapy and local radiation leads to a good clinical outcome with majority having complete response at both primary and metastatic site. The patients with complete response have a relatively better outcome compared to those who don’t. Longer follow up is required in this select group of patients to ascertain the above finding. A. Cortesi 1,2 , A. Galuppi 1 , A. Romeo 2 , G. Ghigi 2 , D.M. Donati 3 , A. Righi 4 , M.E. Abate 5 , G. Bianchi 6 , E. Garofalo 1 , A. Sambri 6 , G. Macchia 7 , F. Deodato 7 , S. Cilla 8 , A.G. Morganti 1 , S. Cammelli 1 1 Radiation Oncology Center- Department of Experimental- Diagnostic and Specialty Medicine - DIMES, University of Bologna- S.Orsola-Malpighi Hospital, Bologna, Italy 2 Radiotherapy Department, Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori IRST- IRCCS, Meldola, Italy 3 Orthopaedic Service- Musculoskeletal Oncology Department-, Rizzoli Orthopaedic Institute, Bologna, Italy 4 Department of Pathology, Rizzoli Orthopaedic Institute, Bologna, Italy 5 Muscolo-Skeletal Oncology Department, Rizzoli Orthopaedic Institute, Bologna, Italy 6 Orthopaedic Service- Musculoskeletal Oncology Department, Rizzoli Orthopaedic Institute, Bologna, Italy 7 Radiotherapy Unit, Fondazione di Ricerca e Cura “Giovanni Paolo II”, Campobasso, Italy 8 Medical Physics Unit, Fondazione di Ricerca e Cura “Giovanni Paolo II”, Campobasso, Italy Purpose or Objective To evaluate clinical outcome during follow-up (FU) in patients with late recurrent soft tissue sarcomas (STS) after adequate surgery, treated with perioperative EP-1628 Radiotherapy for high grade late recurrent soft tissue sarcomas: follow up and outcomes

Conclusion Our results show that refined high-dose photon radiotherapy, following tumour resection by a specialist surgical team, is effective in the long-term control of chordoma and low-grade chondrosarcoma, even in the presence of metal reconstruction. Results presented here will provide a useful source for comparison between high- dose photon therapy and proton beam therapy in a UK setting, in order to establish best practice for the management of chordoma and low-grade chondro- sarcoma. N.R. Khanna 1 , A. Sasidharan 1 , G. Chinnaswamy 2 , T. Vora 2 , J. Bajpai 2 , M. Ramadwar 3 , B. Rekhi 3 , A. Janu 4 , S. Desai 4 , N. Purandare 5 , P. Nayak 6 , A. Gulia 6 , A. Puri 1 , S. Laskar 1 1 Tata Memorial Hospital, Radiation Oncology, Mumbai, India 2 Tata Memorial Hospital, Medical Oncology, Mumbai, India 3 Tata Memorial Hospital, Pathology, Mumbai, India 4 Tata Memorial Hospital, Radiology, Mumbai, India 5 Tata Memorial Hospital, Nuclear Medicine, Mumbai, India 6 Tata Memorial Hospital, Surgical Oncology, Mumbai, India Purpose or Objective Upfront metastatic Ewing Sarcoma (except isolated lung metastasis) has dismal outcome despite aggressive chemotherapy and local treatment. In low resource settings, these patients are offered upfront palliation. Some patients with less extensive disease are challenged with aggressive protocol. There is a lack of guidelines which can help in selecting patients who may benefit with curative intent treatment. Material and Methods After evaluation in a multidisciplinary tumor board, patients were treated with curative intent multimodality treatment comprising of EFT-2001 multi-agent chemo- therapy protocol (induction, concurrent and maintenance phase) and definitive radiotherapy to the primary as well as sites of metastasis. Metastasis within primary tumor portals were treated to a dose of 55.8 Gy in 31 fractions, while the distant metastatic sites were treated with hypofractionated regimen (20 – 33 Gy in 5 to 11 fractions). Results Seventeen patients diagnosed Ewing sarcoma with limited metastatic disease (excluding isolated lung metastases) EP-1627 Outcomes of Ewing Sarcoma with limited metastatic disease treated with curative intent