ESTRO 2025 - Abstract Book

S806

Clinical - Gynaecology

ESTRO 2025

1 Radiation Oncology, Responsible Research Hospital, Campobasso, Italy. 2 Radiation Oncology, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria. 3 Radioterapia Oncologica, Dipartimento di Diagnostica per Immagini, Radioterapia Oncologica Ed Ematologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Roma, Italy. 4 Unità di Ginecologia Oncologica, Dipartimento Scienze della Salute della Donna, del Bambino e di Sanità Pubblica, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Roma, Italy. 5 Gynaecology Oncology, The Royal Marsden NHS Foundation Trust, London, United Kingdom. 6 Radiation Oncology, Leiden University Medical Center, Leiden, Netherlands. 7 Obstetrics and Gynecology, University Medical Centre Groningen, Groningen, Netherlands. 8 Gynecologic Oncology Centre, Department of Gynecology, Obstetrics and Neonatology, First Faculty of Medicine, Charles University and General University Hospital, Prague, Czech Republic. 9 Istituto di Radiologia, Università Cattolica del Sacro Cuore Roma, Roma, Italy Purpose/Objective: Despite updated European Society of Gynaecological Oncology guidelines for vulvar cancer (VC), substantial variability remains in adjuvant radiotherapy practices across European centers due to differences in guideline implementation and unaddressed "grey zones.”. We conducted an international survey among major European reference centers for VC to identify inconsistencies and support standardized approaches to improving patient outcomes. Material/Methods: Fifty-four European VC reference centers completed a survey of 23 items on adjuvant radiotherapy practices, covering target field selection (vulvar, inguinal, pelvic), elective/boost doses, radiosensitizing chemotherapy, and bolus use. Each item offered choices consistent (C) or inconsistent (I) with guideline recommendations and options for “grey zones” (GZ) not covered by guidelines, capturing diverse approaches across centers. Results: Vulvar bed irradiation for local risk factors and/or lymph node metastases was recommended by 58% of centers (C). Notably, 44% routinely irradiated both groins in cases with unilateral groin involvement, considering inguinal regions as a single anatomical area (I). A concordance was observed in the modulation of the radiotherapy field for pelvic nodes based on the extent of disease burden (C). Chemotherapy, primarily weekly cisplatin, showed variable adherence, with only 43% following guidelines (C). While concordance on elective and boost doses was high, 22% delivered different doses to nodal versus vulvar bed (GZ). Boost was delivered to nodes with macrometastases or extracapsular spread by 55% of centers (C), but no consensus emerged on boosts for the vulvar field (GZ). Bolus use was consistent for nodal fields but varied for vulvar areas, depending on the location of the primary tumour (GZ). 80% did not consider the omission of lymph node surgical staging as a single reason for prophylactic radiotherapy (GZ). Conclusion: This study highlights significant variations in adjuvant radiotherapy for VC across European centers. Partial guideline alignment exists, but multicenter studies are needed to address discrepancies. Guidelines could further clarify specific details, supporting more standardized, evidence-based care, including consideration of individual patient and disease factors.

Keywords: Vulvar Cancer, adjuvant radiotherapy, survey

References: Oonk MHM, Planchamp F, Baldwin P, Mahner S, Mirza MR, Fischerová D, Creutzberg CL, Guillot E, Garganese G, Lax S, Redondo A, Sturdza A, Taylor A, Ulrikh E, Vandecaveye V, van der Zee A, Wölber L, Zach D, Zannoni GF, Zapardiel I. European Society of Gynaecological Oncology Guidelines for the Management of Patients with Vulvar Cancer - Update 2023. Int J Gynecol Cancer. 2023 Jul 3;33(7):1023-1043.