ESTRO 2022 - Abstract Book

S1145

Abstract book

ESTRO 2022

Hierro de Majadahonda, Radiation Oncology, Madrid, Spain; 11 Hospital Universitario Reina Sofía, Radiation Oncology, Córdoba, Spain; 12 Hospital Clínico Universitario de Valladolid, Radiation Oncology, Valladolid, Spain Purpose or Objective The present consensus was developed by a team of spanish radiation oncologists on behalf of the subgroup GINECOR of the Spanish Society of Radiation Oncology, (SEOR) to provide a current review of the radiation treatment of VC. A national panel of experts were recruited to reach consensus on the radiation treatment of early and advanced VC. Materials and Methods Prior to the discussion of the statements, we performed an extensive analysis of current medical literature from peer- reviewed journal to define clinical scenarios and evidence-based treatment options. A 2-round web-based modified Delphi study was conducted to reach a consensus on the appropriateness of the different therapeutic options in each clinical setting. The appropriateness of various therapies was classified as appropriate, inappropriate, or uncertain. In those instances where evidence is lacking or not definitive, expert opinion was used to formulate recommendations. Results We recruited 16 radiation oncologist experts from different Spanish regions and clinical setting. Three clinical scenarios were defined: adjuvant treatment locally advanced vulvar cancer and recurrent disease. A questionary of 20 questions regarding indications and technique of radiotherapy was evaluated by panel members to reach consensus on the appropriateness of treatment approaches. Questions are listed in Table. A high level of agreement over 80% was reached.

Conclusion In those aspects of vulvar cancer were evidence is not definitive, expert panel consensous may help in clinical decision- making.

PO-1350 The Effect Of Bladder Volume On Three-Dimensional Vaginal Cuff Brachytherapy Planning

S. Duru Birgi 1 , O.C. Guler 2 , Y. Babayigit 1 , Y. Arslan 1 , S. Akyurek 1

1 ankara University Faculty Of Medicine, Department Of Radiation Oncology, Ankara, Turkey; 2 adana Baskent University, Department Of Radiation Oncology, Adana, Turkey Purpose or Objective OBJECTIVE: It is considered appropriate to simulate an empty bladder and rectum before treatment planning of vaginal cuff brachytherapy. However, the use of a Foley catheter to empty the bladder in each fraction can affect the treatment compliance and quality of life of the patients. In this study, it was aimed to determine the effect of Foley catheter on bladder fullness and the changes caused by the doses received by other critical organs and target volumes in patients who underwent vaginal cuff BRT. Materials and Methods MATERIAL METHODS: Twenty patients with a diagnosis of postoperative endometrial or cervical cancer who underwent 3- dimensional vaginal high-dose rate (HDR-BRT) using a multi-channel cylinder between January 2020 and May 2021 were examined dosimetrically. Rectum emptied using enema in all patients before the first fraction. After evacuation of the urine, two simulation CT scans were performed with and without inserting a foley catheter. Target volumes and critical organs were contoured in accordance with the guidelines in both treatment planning CT scan slices. The treatment plan, which was approved in the planning CT with the Foley, was transferred to the CT withoutFolet, and the dose volume histogram (DVH) parameters were evaluated separately. For both planning, first of all, the volumes of HRCTV and critical