ESTRO 2020 Abstract book

S704 ESTRO 2020

Material and Methods All patients undergoing RT at the department of radiation oncology at our center are seen regularly for follow-ups after RT following a strict recall system. Therefore, clinical follow-up is available and documented prospectively in our electronic patient record system. Cut off for early death after RT was defined as death within 90 days after last RT. Patients with early death after RT treated between July 2018 and September 2019 were included in the analysis. Results We identified 32 patients from our database according to the defined inclusion criteria, of which 12 were female and 20 male. Median Karnofsky Index at the beginning of RT in these patients was 60% (range 20). 10 out of 32 patients were treated for bone metastases, 5 patients had a carcinomatous meningitis, 5 patients suffered from head and neck cancer and 3 patients were treated for brain metastases. 25 of all patients suffered from metastatic disease and 29 out of 32 patients were treated in palliative intention. 28 patients got a hypo-fractionated RT e.g. with a single dose of 2,5 Gy (3 patients), 3 Gy (16 patients) or 4 Gy (5 patients). Mean survival time in these patients after RT was 27 days, median survival time was 17 days. 12 patients terminated RT too early. 8 of these patients got worse under RT, 4 patients decided to quit RT at their own request. In most cases progressive tumor disease was the reason for early death after RT. 13 patients had an immediate benefit in the end of RT (e.g. reduction of pain/tumor bleeding). Conclusion In 29 of 32 patients RT was applied in palliative intent to relieve cancer related symptoms e.g. tumor bleeding or pain. These are well-accepted indications for RT and may explain early death in this group. Fortunately only up to 1% of all patients treated in the department of radiation oncology at the TUM in that year died within 90 days after RT, which reflects the careful patient selection for RT as well as the patient case-mix in a university-based setting. RT is better tolerated due to the use of modern RT and provides effective palliation in certain cases. Furthermore multidisciplinary selection criteria in patients undergoing RT seem to be appropriate. The data are going to be evaluated in a multicenter project. PO-1248 Preliminary safety and survival report of Stereotactic radiotherapy to oligometastases. N. Hanumanthappa 1 , C. Goldsmith 1 , V.M. Mullassery 1 , S.L. Morris 1 , A. Aggarwal 1 , B. Taylor 1 , A. Gaya 1 , D. Smith 1 , E. Dunne 1 , T. GuerreroUrbano 1 , A. Qureshi 1 , V. Staykova 2 , C. Thomas 2 , C. Williams 3 , C. Hartill 4 , L.H. Taylor 4 , V. Harris 1 , C. Edwards 2 , V. Grandi 5 , S. Vivekanandan 1 , C. Sisodia 2 , S. Ahmad 1 1 Guy's and St Thomas's NHS Trust Hospital, Clinical Oncology, LONDON, United Kingdom ; 2 Guy's and St Thomas's NHS Trust Hospital, Medical Physics, London, United Kingdom ; 3 Guy's and St Thomas's NHS Trust Hospital, Radiology, London, United Kingdom ; 4 Guy's and St Thomas's NHS Trust Hospital, Radiotherapy, London, United Kingdom ; 5 St Johns Institute of Dermatology, Dermatology, London, United Kingdom Purpose or Objective To report toxicity and patient/treatment related variables influencing survival outcomes of Stereotactic ablative body radiotherapy (SABR) treatment in patients treated at a single institution for oligometastatic disease due to various primary malignancies. Material and Methods Clinical Data was reviewed for the first 91 consecutive patients treated with LINAC-based SABR for oligometastases from January 2015 to December 2018 within Commissioning through evaluation programme, to evaluate toxicity and factors driving overall survival (OS).

1 Ospedale San Raffaele IRCCS, Radiotherapy, Milan, Italy ; 2 Ospedale San Raffaele IRCCS, Medical Physics, Milan, Italy ; 3 Vita-Salute University, Medical and Surgery Department, MIlan, Italy Purpose or Objective The treatment of spine and bone metastases with standard external beam radiotherapy ensures a six months symptomatic and local control, which could be insufficient for long term survival oligometastatic patients (pts). Recent studies demonstrated long term pain and local control by dose intensification delivered with stereotactic body radiotherapy (SBRT). The aim of this study is to report clinical effectiveness and safety of SBRT using Cyberknife in spinal and bone metastases. Material and Methods From October 2017 to September 2019, 97 pts with 134 oligometastatic/oligoprogressive bone metastases were treated with Cyberknife in our Institution: 79% were spinal lesions, while 21% were non-spine. The most common primary sites were: prostate 61.9%, breast 12.7%, lung 8.9%, kidney 7.4%, bladder 2.9 %. Pain was present before SBRT in 32% of pts with a median value of 5 (3-8), according to Visual Analogue Scale (VAS). Two mg of dexamethasone were prescribed in more than half of pts for 1 week during and after the treatment. In the majority of pts with spinal lesions CT, T1 and T2 MRI were fused and used to outline the gross tumor volume (GTV), to maximize tumor coverage and minimize spinal cord exposure. GTV to planning target volume (PTV) expansion was 2 mm. Median dose prescription was 18 (16-35) Gy, delivered in a median of one fraction (1-7). Results All patients were able to maintain the position during treatment delivery for a median treatment time of 52 minutes (28-83). Median follow-up was 5 (1-17) months. Early pain relief was observed in all symptomatic pts. Only two of 97 patients presented local progression disease. One patient developed G2 acute pain flare toxicity (according to CTCAEv4.03), after one day of dexamethasone suspension. The pain was controlled prolonging dexamethasone for two additional days. In 66 lesions with a follow up longer than 3 (3-17) months, no late toxicities and SBRT-related fractures were observed. Conclusion Our experience with dose intensification in bone metastases is consistent with other published studies, which demonstrated that bone SBRT is a safe treatment providing mild acute and late toxicity profile and early pain relief in all pts. A longer follow up is necessary to confirm the very good local control. R. Asadpour 1 , S.U. Pigorsch 1 , C. Straube 1 , S.E. Combs 1,2,3 1 TU Munich, Department of Radiation Oncology, Munich, Germany ; 2 German Consortium for Translational Cancer Research dktk, Partner Site Munich, Munich, Germany ; 3 Institute of Innovative Radiotherapy iRT, Department of Radiation Sciences DRS- Helmholtz Zentrum München, Munich, Germany Purpose or Objective Radiotherapy (RT) is a main pillar in cancer care. During their course of disease, over 50% of tumor patients are treated with RT, whether in curative or palliative intent. Indication for RT depends on many factors, for example patients’ performance status, life expectancy but also on the expected gain of therapy in terms of palliation. However, due to several factors, early death after RT is observed in some patients. To understand the reasons for early death after RT and to develop potential changes in indications and practice patterns, we analyzed patients at the Technical University of Munich (TUM) treated with RT between July 2018 and September 2019. PO-1247 Analysis on early death in patients after radiotherapy: Should we change practice?