ESTRO 36 Abstract Book

S300 ESTRO 36 _______________________________________________________________________________________________

M. Coffey 1 1 Coffey Mary, Dublin, Ireland

and often they are offered palliative radiotherapy. Although palliative radiotherapy is effective in symptom reduction in most patients, the duration of benefit is limited. Importantly, there are situations that patients might benefit from a more radical approach using radiotherapy alone, with the aim to provide durable local control. With standard external beam (chemo)radiotherapy (EBRT, 45-50 Gy), complete pathologic response (pCR) is reached in approximately 16%. But dose response analyses indicate that a high dose of more than 90Gy (EQD2) is needed to achieve pCR in 50% of patients. EBRT with either contact-X-ray or endorectal high-dose-rate brachytherapy have been used in these situations. Outcomes of these approaches for local control and toxicity will be reviewed followed by an update of ongoing studies. SP-0562 Breast cancer I. Kunkler 1 1 Western General Hospital- Edinburgh Cancer Centre, Edinburgh, United Kingdom The evidence base for postoperative radiotherapy after mastectomy and after breast conserving surgery (BCS) and for accelerated partial breast irradiation (ABPI) is limited in older patients. This reflects in part historical exclusion of patients >70 years from many trials or trials which included but were not confined to older patients. The Oxford overview (1) shows that postmastectomy radiotherapy (PMRT) reduces local recurrence and breast cancer mortality in women with 1-3 positive nodes as well as 4 or more positive nodes. However the role of PMRT in women with 1-3 involved nodes remains controversial. The current MRC/EORTC SUPREMO trial and its translational substudy TRANS-SUPREMO (2) is addressing this issue and has no upper age limit. There is a need to refine the selection of patients for PMRT on a biological basis with the aid of molecular markers (3). There is consensus that shorter, hypofractionated schedules of whole breast RT (WBRT) in 15 or 16 fractions are appropriate for older patients. Recent 20 year follow up of the EORTC ‘boost’ trial shows no statistically significant advantage in local control from the addition of a 16 Gy boost to the site of excision after WBRT (4) in women over the age of 60. There is a developing level 1 evidence base to suggest that omitting postoperative WBRT in ‘low risk’ older patients after BCS is an option but the issue remains controversial. The CALGB 9343 trial in T1,NO women =/>70 yrs showed a 3% reduction in loco-regional recurrence at 5 years (1% vs 4%) and 7% at 10.5 years (2% vs 9%)[5,6]. However, while the early results changed NCCN guidelines to allow the omission of WBRT in patients meeting the eligibility for the CALBG trial, international practice has not changed substantially with WBRT remaining standard, irrespective of risk category. The recent PRIME 11 trial in a higher risk of group of patients =/>65 years (T1-2 [up to 3cm],NO) showed a modest but statistically significant reduction in ipsilateral breast tumour recurrence from WBRT after BCS at a median follow up of 5 years (1.3% vs 4.1%) [7]. Whether this difference is sufficiently small to change practice remains to be seen. Current studies such as PRIME-TIME (8) in the UK and PRECISION (9) in the US focus on assessing the role of biomarkers to refine the selection of ‘low risk’ patients for omission of postoperative radiotherapy after BCS in older patients. None of the four published trials on ABPI to date, using a variety of techniques (brachytherapy, external beam,intraoperative irradiation) were confined to older patients, allowing limited conclusions in this age group. 1. EBCTCG. Effect of radiotherapy after mastectomy and axillary surgery on 10 year recurrence and 20 year breast cancer mortality: meta-analysis of individual patient data for 8135 women in 22 randomised trials. Lancet 2014;383:2127-35.

New roles in advanced practice for RTTs In a dynamic field such as radiotherapy it is essential that all professionals are equipped to assume evolving roles and responsibilities that reflect changing practice. From a professional and clinical perspective the RTT, as an autonomous member of the team, must take equal responsibility for the introduction of change in their working environment. To enable this the ESTRO RTT committee have produced the ESTRO RTT Education Qualification Framework (EQF) for level 7 and 8. This has identified a number of key areas where advanced roles and responsibilities taken by RTTs will effectively support the dynamic clinical changes in radiotherapy preparation and delivery. On a professional level 7 and 8 will support the development of research options for practice improvement placing the RTT on an equal platform with their professional colleagues. Links to the underpinning academic topics to facilitate the development of these roles have been made. Linking academic content and evolving roles and responsibilities enables the RTT to take his/her place as an equal member of the team by providing the appropriate knowledge and skills that enable critical evaluation of practice. Defining academic components at level 7 and 8 provides a framework for staged role development combining academic components with clinical experience. The descriptions of level 7 and 8 within the ESTRO EQF are consistent with the level descriptors defined in the European Qualifications Framework. Level 7 is described as “highly specialized knowledge, some of which is at the forefront of knowledge in a field of work or study, as the basis for original thinking and/or research …. a critical awareness of knowledge issues in a field and at the interface between different fields”[1]. Level 8 is described as ‘knowledge at the most advanced frontier of a field of work or study and the interface between fields’ providing the skills and competences of “the most advanced and specialist skills and techniques, including synthesis and evaluation, required to solve critical problems in research and/or innovation and to extend and redefine existing knowledge or professional practice”[2]. The advanced roles include treatment planning, patient support, management and research amongst others. RTTs across Europe have already embraced many of the advanced roles and responsibilities and by providing this framework it is hoped to provide a roadmap for others to follow suit. [1] https://ec.europa.eu/ploteus/content/descriptors-page [2] Ibid SP-0561 Radiotherapy in elderly rectal cancer patients R. Nout 1 1 Leiden University Medical Center LUMC, Department of Radiotherapy, Leiden, The Netherlands The incidence of rectal cancer is increasing in elderly patients due to effects of population screening and aging. Total mesorectal excision (TME) surgery with or without pre-operative radio(chemo)therapy is the standard treatment for rectal cancer. However, with increasing age and co-morbidity the risk of surgical complications and post-operative mortality rises. In patients older than 75 years, and especially above 80, postoperative complications occur in approximately 50% and postoperative mortality is increased. In these situations, the risks of postoperative complications and mortality may render patients unfit for surgery. For the same reasons these patients are usually also unfit for chemotherapy, Symposium: Radiotherapy in the elderly