ESTRO 37 Abstract book

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ESTRO 37

17 (19.1%) patients,respectively. Any type of recalsification response was obtained in 86 (96.7%) patients.Complete and partial radiologic recalsification response was recorded in 45 (50.6%) and 41 (46.1%) patients, respectively. Of the patients who had complete response radiologically, 9 (81.8%) were SP and 36 (46.1%) were MM (p=.025). The major difference was total RT dose between these two groups. When the radiologic recalsification response was evaluated in terms of total radiation dose, complete response was significantly higher in total 45 Gy RT doses than 30 Gy doses (p<.001). Local control was obtained in 82 (92.1%) patients. 7 (7.9%) patients experienced disease progression during the follow-up and times to local progression were 7, 9, 11, 12, 72, 84 and 119 months. In median 23 months follow-up period, 2-year local control rate for whole group, SP and MM were 94%, 100% and 93%, respectively (p=.384). Conclusion RT has an important role in PCTs for obtaining pain relief, preventing pathologic fractures and reducing analgesic intake. Additionally, remodulation in bones may be considered as a secondary but long term goal for radiotherapy. Our data showed that adequate pain relief and recalsification effects could be supplied with minimum 30 Gy total doses and one should wait minimum 6 months for the recalsification response to RT. Our trial is important in terms of using objective methods for both pain relief and recalsification response. EP-1699 Low-Dose Radiotherapy For Management Of Lymphorrhea A. Alvarez-Gracia 1 , A. Arellano 1 , I. Planas 1 , A. Mañes 1 , J. Jové 1 , Y. Luis 1 , H. Rosales 1 , G. Antelo 1 1 ICO - Hospital Universitari Germans Trias i Pujol, Radiotherapy Oncology, Badalona, Spain We performed a retrospective study of 10 patients treated with Radiotherapy between 2007 and 2017 with persistent inguinal lymphorrea, which did not improve with local treatment. In 9 patients lymphorrea was secondary to vascular/cardiac surgery and in 1 patient was secondary to inguinal surgery for penile neoplasia. Mean age was 67 years. Three patients were female and seven were male. The treatment was designed by CT and 3D-CRT technique was used. The volume of treatment included the entire lymphocele volume and a safety margin. Seven patients were treated with LINAC with 6 and 18-MV photons and three patients with a direct 16- MeV electron field. Median total dose was 2,9 Gy (0,45- 9) and median fractionation dose was 0,15 Gy/fx (0,1- 1,5). Purpose or Objective Material and Methods

Results 9 of the patients treated, had permanent cessation of lymphorrea and in only one patient, the Radiotherapy was not effective. Side effects were not observed during treatment. At three months of follow-up, complete cessation of lymphorrea was observed in all patients (except in the one patient who did not respond to Radiotherapy)and only grade 1 subcutaneous fibrosis was observed in one patient (who received 9 Gy), while the rest did not show any toxicity. Conclusion Inguinal lymphorrea can be treated with low doses of Radiotherapy and without side effects. Radiation therapy should be considered as a treatment option in patients with this post-surgery complication. EP-1700 Quality benchmarking in hyperthermia treatment. A. Di Dia 1 , C. Bracco 1 , S. Bresciani 1 , G. Cattari 2 , A. Maggio 1 , A. Miranti 1 , P. Gabriele 2 , M. Stasi 1 1 Candiolo Cancer Institute -IRCCS, medical physics, Candiolo, Italy 2 Candiolo Cancer Institute -IRCCS, Radiotherapy Department, Candiolo, Italy Purpose or Objective The development of performance indicators for certification/accreditation systems and quality benchmarking is evolving. The aim of this work is to provide a set of quality indicators for hyperthermia (HT) treatments in order to make a continuous quality improvement. Material and Methods A preliminary set of indicators was selected on the basis of evidenced critical issues. Three structure, six process and two outcome quality indicators were obtained. A multidisciplinary team (Radiation Oncologist, Medical Physicist and Radiation Technologists) was assembled in order to underline main critical issues in the use of hyperthermia. Results A final set of 11 indicators has been developed. For each indicator, topic, type of indicator, numerator (parameter value),denominator (reference population), standard (reference value), and frequency of analysis have been proposed. Numerical values for the standard were selected from the international literature, when available, and from guidelines on hyperthermia/radiotherapy, or empirically on the basis of the experience of the Italian Institutes (Table 1).