ESTRO 37 Abstract book

S907

ESTRO 37

(image-guided radiation therapy; IGRT) have improved the delivery of the dose while particle radiotherapy with protons or heavier ions has emerged as an interesting technology in radioresistant tumors in close proximity to organ at risk, when it is desired to spare growing organs from irradiation. Still, there is a high unmet medical need to enhance the energy dose deposit within tumor cells without increasing the dose received by surrounding healthy tissues. Material and Methods Hafnium oxide nanoparticle (NBTXR3), a high electron density nanoparticle, has been specifically designed to address this high unmet medical need. Monte Carlo simulations using either photons or particles (protons) radiotherapy have proved the fundamental concept of local enhancement of energy dose deposit using high electron density nanoparticles. The designed NBTXR3 nanoparticles increase the probability of interaction with incoming radiations to enhance the energy dose deposition from within tumor cells. They present a favorable ratio of X-ray absorption for an efficient cell killing to toxicity. Results NBTXR3 administered as a single intratumoral injection and activated by photon radiotherapy is currently evaluated in several clinical trials, including a phase II/III in soft tissue sarcoma (STS) [NCT02379845] and phases I/II for head and neck [NCT01946867], prostate [NCT02805894], liver [NCT02721056] and rectum cancers [NCT02465593]. So far, 142 patients treated with NBTXR3 received radiotherapy as planned, with a good local safety profile. All data generated showed interesting transferability across different cancer indications. These first-in-class nanoparticles show promising results in terms of antitumor efficacy in patients with locally advanced STS and head and neck squamous cell carcinoma. Furthermore, in preclinical studies, NBTXR3 exposed to radiotherapy has demonstrated substantial enhancement of immunogenic cell death and improvement of the immune response when compared to radiotherapy alone suggesting it could function as an effective in situ tumor vaccine. Conclusion In conclusion, NBTXR3 intended use fit perfectly with existing and under development radiotherapy technologies offering unique opportunity to widen the therapeutic window of radiation oncology. Beyond, it may efficiently combine with immunotherapeutic agents across oncology. EP-1687 The current place of radiotherapy as treatment option for muscle-invasive bladder cancer. E. Rammant 1 , K. Decaestecker 2 , Y. Lievens 3 , P. Dirix 4 , P. Sargos 5 , M. Vedang 6 , L. Eapen 7 , J. Christodouleas 8 , On behalf of IBIS group 9 , V. Fonteyne 3 1 Ghent University, Radiotherapy and experimental cancer research, Gent, Belgium 2 Ghent University Hospital, Urology, Gent, Belgium 3 Ghent University Hospital, Radiotherapy and experimental cancer research, Gent, Belgium 4 The Antwerp University Hospital, Department of Radiation-Oncology, Antwerp, Belgium 5 Institut Bergonie, Département de Radiothérapie, Bordeaux, France 6 tata memorial centre, departement Radiation-oncology, Mumbai, India 7 The Ottawa Hospital, Regional Cancer Centre, Ottawa, Canada

articles were published within 2 years and 80% within 3 years of presentation; lower than that reported over the 1996-1999 period of 68% at 2 years and 93% at 3 years respectively. There was an increase in the diversity of journals in which abstracts were published, with published abstracts from 2010-2013 appearing in 143 journals. Conclusion There has been improvement in APR for abstracts at RANZCR annual meetings in the intervening decade between analyses, with the largest increase in publication being radiation oncology themed abstracts. Publication rates are comparable with international series in an increasingly diverse number of journals. Increasing publication rates should encourage future authors of oral presentations or poster abstracts to develop manuscripts for publication. and radiotherapy for solid tumors: a promising new treatment strategy C. Le Tourneau 1 , C. Le Pechoux 2 , G. Kantor 3 , S. Carrere 4 , S. Bonvalot 1 , E. Le Prise 5 , F. Nguyen 2 , A.S. Baumann 6 , V. Vendrely 7 , J.P. Bronowicki 8 , V. Moreno-Garcia 9 , M. Delannes 10 , J. Thariat 11 , Z. Papai 12 , P. Ruthowski 13 , B. Tiangco 14 , M. Rastrelli 15 , P. Agoston 16 , M.P. Sunyach 17 , K. Rubi Li 18 , A. Mervoyer 19 , T. Sy-Ortin 20 , A. Hong 21 , R. Anghel 22 , A. Gronchi 23 1 Institut Curie, Oncology, Paris, France 2 Institut Gustave Roussy, Oncology, Villejuif, France 3 Institut Bergonié, Oncology, Bordeaux, France 4 ICM, Oncology, Montpellier, France 5 Eugène Marquis, Oncology, Rennes, France 6 Cancérologie de Lorraine, Oncology, Nancy, France 7 Hôpital du Haut-Lévêque, Oncology, Bordeaux, France 8 Hôpitaux de Brabois CHU Nancy, Oncology, Nancy, France 9 START Madrid, Oncology, Madrid, Spain 10 Claudius Regaud, Oncology, Toulouse, France 11 Antoine Lacassagne, Oncology, Nice, France 12 Medical Centre- Hungarian Defence Forces, Oncology, Budapest, Hungary 13 Centrum Onkologii-Instytut im. Sklodowskiej-Curie w Warszawie, Oncology, Budapest, Hungary 14 The Medical City, Oncology, Pasig City, Philippines 15 Institute of Oncology Veneto IOV, Oncology, Padova, Italy 16 Országos Onkológiai Intézet, Oncology, Budapest, Hungary 17 Centre Léon Bérard, Oncology, Lyon, France 18 St. Luke's Medical Center, Oncology, Quezon City, Philippines 19 Centre Rene Gauducheau- CLCC Nantes Atlantique, Oncology, St Herblain, France 20 University of Santo Thomas, Oncology, Manila, Philippines 21 Chris O'Brien Lifehouse, Oncology, Sidney, Australia 22 Institutul Oncologic Bucuresti- “Prof. Dr. Alexandru Trestioreanu”, Oncology, Bucharest, Romania 23 Fondazione IRCCS Istituto Nazionale dei Tumori, Oncology, Milan, Italy Purpose or Objective Technological advances in radiation oncology over the past decade have focused on high-precision radiotherapy to reduce unwanted irradiation of normal tissues, while fully covering the tumor. Techniques in photon radiotherapy such as intensity- modulated radiation therapy (IMRT) and image guidance EP-1686 Hafnium oxide nanoparticles