ESTRO 2022 - Abstract Book

S510

Abstract book

ESTRO 2022

Conclusion Assessment of interfractional rectum filling led to adaptive planning in approx. 17% of patients. Dose distributions between rectum and rectum_adapt vary significantly in higher doses (V50 and 60). The clinical benefit of the proposed offline adaptive-planning strategy should be evaluated in larger cohorts.

PD-0582 Phase II trial of SBRT for adrenal metastases: efficacy and impact on hormonal production.

C. Franzese 1 , S. Stefanini 1 , M. Massaro 1 , T. Comito 2 , P. Navarria 2 , E. Clerici 1 , A. Teriaca 2 , D. Franceschini 2 , G. Reggiori 2 , S. Tomatis 2 , A. Lania 3 , M. Scorsetti 1 1 Humanitas University, Humanitas Research Hospital IRCCS, Radiotherapy and Radiosurgery, Milano, Italy; 2 Humanitas Research Hospital IRCCS, Radiotherapy and Radiosurgery, Milano, Italy; 3 Humanitas University, Humanitas Research Hospital IRCCS, Endocrinology, Diabetology and Medical Andrology Unit, Milano, Italy Purpose or Objective The purpose of this study was to assess prospectively the efficacy and safety of Stereotactic body radiation therapy (SBRT) for adrenal gland metastasis, with a focus on the assessment of the irradiated subjects’ endocrinological function. Materials and Methods A total of 36 patients were enrolled from 2017 to 2020 in this prospective phase II trial. Patients were treated with Linac- based SBRT, with a dose of 45 Gy in 3 consecutive fractions. Primary end-point was local control (LC) of the treated lesions and secondary end-points included evaluation of acute and late toxicity, progression free survival (PFS), overall survival (OS) and the impact on the hormonal production of adrenal glands. Results With a median follow-up of 9.5 months, LC rates at 1 and 2 years were 94.7% and 88.4%, respectively. Rates of PFS at 1 and 2 years were 50.5% and 29.8%, with a median PFS of 14.7 months. Rates of OS at 1 and 2 years were 62.9% and 44.1%. At univariate analysis, oligorecurrence was associated with better OS compared to oligoprogressive or synchronous metastatic disease. No grade 3 or greater toxicities were registered and only a minority of patients (22.2%) reported mild treatment-related side effects. Hormonal and electrolytes production was assessed before and after treatment, showing only a slight and transient variation within the reference ranges. Conclusion SBRT on adrenal metastases has been confirmed to be a feasible and effective treatment. With an excellent disease control and the preservation of the endocrine function, SBRT with ablative dose can be considered a viable alternative to more invasive approaches

Award Lecture: Honorary Physicist Award

SP-0584 TBC

C. Faivre-Finn

United Kingdom Abstract not available