ESTRO 37 Abstract book

S351

ESTRO 37

SP-0672 Salvage prostate radiotherapy: when and how? B.A. Jereczek-Fossa 1 1 Università degli Studi di Milano - European Institute of Oncology,Oncology&hemato-oncology Dept/Radiotherapy Dept. of European Institute of Oncology, Milano, Italy Abstract text External beam radiotherapy (EBRT) is widely used as primary treatment for localized prostate cancer (PCa). A recently published randomized PROTECT study with a median 10-year follow-up, demonstrated that in localized low and intermediate risk prostate cancer, EBRT achieves similar results to radical prostatectomy in terms of tumor control and specific mortality. In recent years the development of modern techniques as intensity modulated radiation therapy (IMRT), image-guided radiation therapy (IGRT) and stereotactic body irradiation (SBRT), added to the progressive dose escalation of prescribed and delivered radiation, have been associated with good local control of the tumor and enhanced overall survival in patients affected by localized prostate cancer. However, still approximately 22 – 60% of patients develop biochemical failure after radical EBRT. Currently, the standard treatment for locally recurrent PCa is not defined, different therapeutic options are available and include: systemic therapy (androgen deprivation therapy: ADT) or local salvage approaches with curative intent as salvage prostatectomy, re- irradiation, cryotherapy, high intensity focused ultrasound (HIFU). The majority of the series are small and include heterogeneous patients and treatments without a long follow-up. No randomized trials comparing salvage local and systemic strategies are available. The most effective local therapy has not been established and remains controversial in the absence of consensus. The patients with biochemical failure receive mainly long lasting ADT with negative impact in the quality of life. In selected patients with locally recurrent PCa, PSA < 10 ng/ml and a good life expectancy (>10 years) a local treatment with radical intent can be considered. However, numerous case series and large databases show that local salvage therapy is dramatically underused. This underuse of local salvage therapies can be explained by several issues including advanced patient age and presence of numerous comborbidities, lack of prospective studies in this area and fear of side effects of re- treatment employing both surgical and non surgical approach. Indeed, the primary RT dose prescribed for prostate cancer is already high (dose escalation), thus re- irradiation might lead to severe injury of surrounding organs like rectum and urinary bladder. Until recently, the vast majority of re-irradiation series included patients treated with brachytherapy (BRT). In the last years, along with the improvement in RT planning and delivery technology, first reports on salvage EBRT (re- EBRT) have been published (9 published series: Vavassori et al 2010, Zerini et al 2015, Fuller et al 2015, Zilli et al 2016, Rutenberg et al 2016, Janoray et al 2016, Detti et al. 2016, Leroy et al. 2017). Use of modern approaches like image guided stereotactic (SBRT) re-irradiation, offers a high precision in delivery of radiation dose to small targets minimizing the dose to the organs at risk (OAR). All these series show that Re-EBRT delivered with modern techniques like IMRT and SBRT is a safe, feasible and noninvasive treatment for the well selected locally recurrent PCa, offering a satisfactory tumor control (about 50-60% of the patients are free of progression at 2 years) and excellent toxicity profile. Further investigation is warranted to define the optimal patient selection and establish the optimal dose and volume parameters for this particular clinical scenario.

population will have to be incorporated in future clinical practice. Apart from the general challenges of performing economic evaluations in a technology driven discipline such as radiation oncology, there are some aspects specific for the elderly cancer population that have to be taken into account. With age, changes in clinical characteristics and tumour behavior occur and treatment tolerance could be worse. Furthermore, patient preferences will be different than for the younger population. These changes will influence the costs and outcome of a certain treatment. Hereby, a treatment which is deemed cost-effective for the general popu- lation might not be cost-effective for the elderly subgroup and the other way around. Effectively, age can have an influence on all parameters that form the input for an economic evaluation.* On the cost side, it may influence the resource utilization rate, while on the effect side it may influence baseline risks (for example the chance of tumor recurrence), the treatment effect and health state utility scores, that are influenced by eg toxicity and preservation of functionality. Furthermore, these parameters can vary even for subgroups within the elderly population itself, as preferences and treatment outcome will be different for fit compared to vulnerable or frail patients. In order to reliably inform policy makers and optimize resource use, efforts should be made to collect individual patient data in the elderly population, including utility scores and results of geriatric screening/assessment. In this presentation, the influence of age on treatment decisions will be discussed, and through some practical examples of ongoing clinical trials, insight/recommendations will be given on how to obtain evidence on cost effectiveness of radiotherapy treatment in the elderly population. * J. Grutters, M. Sculpher, A. Briggs, et al: Acknowledging patient heterogeneity in economic evaluation : a systematic literature review. Pharmacoeconomics. 2013 Feb;31(2):111-23. SP-0671 Quality of Life in cancer patients in clinical trials in the radiation oncology setting A. Bottomley 1 1 EORTC, Quality of Life, Brussels, Belgium Abstract text Quality of life is a common endpoint in cancer clinical trials and often with elderly patients. The aim of this talk will be to briefly define what Quality of Life means, how it is best assessed and what are the key drivers of the Quality of Life movement in oncology and with the elderly patient. The talk will address tools that can be used in the elderly, and in patients undergoing radiation therapy. As an example, results of a new systematic review will be presented, detailing a critical evaluation of quality of life in clinical trials of breast cancer patients treated with radiation therapy. Furthermore, the presentation will highlight new methods to access Quality of Life and side effects and present the new EORTC electronic Item Library which aims to make adaptive checklists of tools that can be tailored for each trial, and added to standardized tools, to ensure that we capture the patient experience to the fullest extent. The presentation will also highlight challenges that researchers face when undertaking trials with Quality of Life, and where methodological design and analysis shortfalls have hindered the use, interpretation and uptake of Quality of Life in Randomized Controlled Trials. Several solutions will be proposed and discussed.

Symposium: Salvage prostate radiotherapy