ESTRO 38 Abstract book

S57 ESTRO 38

Conclusion Our data suggest contemporary CIEDs being safe during low energy RT exposure,withstanding photon doses up to 10 Gy, since, a part from transient electromagnetic interferences, no major malfunctions were observed.

target angle enhance the PVDR and the treatment depth. After experimental validation of our results, our source will be applicable to both in vitro and in vivo research. PV-107 In vitro study of CIEDs malfunctions by direct exposure at doses≥2Gy M.D. Falco 1 , E. Di Girolamo 2 , C. Di Carlo 1 , N. Adorante 1 , G. Caravaggio 1 , S. Marcucci 1 , D. Genovesi 1 1 “G. D’Annunzio” University- “SS. Annunziata” Hospital, Department of Radiation Oncology, Chieti, Italy ; 2 "SS. Annunziata” Hospital, Heart Department- Arrhythmology Unit, Chieti, Italy Purpose or Objective Exposure to high dose photon beams for oncologic radiotherapy (RT), at even less than 6MV power,has been reported to potentially lead to transient or permanent, even life-threatening, malfunction in patients having a cardiac implantable electronic device (CIED), both pacemaker (PM) or implantable cardioverter-defibrillators (ICD), implanted. To date, the effects of RT on CIEDs is not that predictable, depending on multiple factors and variables. To evaluate potential CIED malfunctions by direct exposure to doses up to 10 Gy in RT,100 PMs and 40 ICDs with at least 4 months to Elective Replacement Indicator (E.R.I.), were referred for study. Material and Methods All CIEDs underwent baseline interrogation. Single chamber CIEDs were programmed in the VVI/40 mode and dual or triple chamber ones were programmed in the DDD/40 mode. Rate adaptive function was disabled. In ICDs, antitachycardia therapies were disabled with the ventricular tachycardia (VT)/ventricular fibrillation (VF) detections still working. As in patients, a centering Computed Tomographywas performed to build the corresponding treatment plan. CIEDs were blinded randomized to either 2, 5 or 10 Gy exposure by a low photon-energy Linear Accelerator (6MV) in a water phantom (600 Um/min). An in-vivo EPID dosimetry was performed by the medical physicist to assess the effectiveness of the dose received by the CIEDs. During exposure, 22 wireless-enabled devices were observed and recorded in a real-time session using manufacturer- specific equipment. All CIEDs had telemetry-interrogation immediately after exposure and monthly follow-up for three months. Results During exposure, most wireless-enabled CIEDs (90.9%) recorded electromagnetic interferences. 6 ICDs (27.3%) reported major interferences with even ventricular oversensing, basic-rate-pacing inhibition and VT/VF detection. Immediately after exposure, in less recent CIEDs, a reset to emergency mode was observed in a PM (0.7% overall, 1% among PMs), while 7 PMs (5% overall, 7% among PMs) reached an unexpected E.R.I. During the three-month follow-up, 3 PMs (2.2% overall; 3% among PMs) reached the E.R.I. and 1 PM reporteda reset to emergency mode. All the permanent malfunctions observed in our series, occurred in only less recent CIEDs (see Table 1).

Award Lecture: Emmanuel van der Schueren Award Lecture

SP-0108 Learning from clinical practice: pushing quality forward N. Jornet 1 1 Hospital de la Santa Creu i Sant Pau, Medical Physics, Barcelona, Spain Abstract text “I am a clinical medical physicist”. You hear this quite often in scientific meetings, many times in contraposition of “research medical physicist”. Is there a disruption between clinical work and research?I do think that the gap between clinically and research oriented radiation oncology professionals and in particular medical physicists should be closed. Clinical Medical Physicists are co-responsible with RTTs and Radiation Oncologists of guaranteeing that treatments are planned and delivered safely and with high quality standards. That sounds great, but quality assessment in Radiation Oncology is still not implemented in many departments and therefore is still difficult to agree on quality standards to which all should aim to. The lack of structured data collection in most departments does not only make difficult to judge quality but also jeopardises technology evaluation in our area. During the last decades, we have been implementing new techniques and technologies. However, it is difficult determine whether these efforts have had an impact on the survival and quality of life of the patients. Differently from other medical disciplines, preclinical evidence as well as randomised trials are scarce and therefore technology is implemented, in some cases, based on planning studies. But, even if the dose distribution is “better”, we still need to know if there is a real benefit for the patient as well as for efficiency (i.e. patient turnout) and safety. Research cannot, and should not, be unlinked from clinical practice. Clinically oriented radiation oncology proffessionals should be committed to data analysis in order to assess quality, perform technology assessment and also to advance in predictive models that will ease the optimal selection of treatments for our patients. By collecting Quality Indicators and by sharing data between institutions, regions and countries, quality standards can be set and harmonisation of practice can become a reality. During this talk I would like to share with the audience some thoughts: 1. Quality assessment is a must in any radiotherapy department. We need to know how our practices, tolerances, action limits have an impact in the patients we treat. 2. Research and clinical practice is not only possible but should be facilitated in all departments. 3. Structured data collection and analysis in all departments is the only way to evaluate quality and monitor if technological improvements have an impact on patient’s quality of life. 4. Collaborative work at institutional, regional, national and international level in quality assessment projects is key to advance towards the paradigm of delivering the radiation therapy with the same quality standards across departments. I would like to finish quoting Professor van der Schueren: “Even major improvements have been shown to take up to 10 years to be applied. The treatment needs to be