{"paper_id":"280b44cb-b06c-4222-b251-6ea41df6d0fd","body_text":"ECR 2026 / C-13946\n68GA-BED003 FAP-targeted PET/MRI for endometriosis assessment - initial results\nCongress:\nECR 2026\nPoster Number:\nC-13946\nType:\nScientific Exhibit\nKeywords:\nGenital / Reproductive system female, Hybrid Imaging, Nuclear medicine, MR, PET-CT, PET-MR, Molecular imaging, Inflammation\nAuthors:\nJ. Brandt, P. Backhaus, D. Ventura, S. Eltrop, P. Schindler\nDOI:\n10.26044/ecr2026/C-13946\nPurpose\nEndometriosis is a common gynecologic disorder often associated with chronic pelvic pain, infertility and reduced quality of life (1). Conventional imaging modalities such as transvaginal ultrasound and MRI may underestimate the extent of disease, particularly in deep infiltrating endometriosis (DIE) (2,3). Fibroblast activation protein (FAP) is highly expressed in remodeling tissues and an emerging target for molecular imaging and therapy in cancer using FAP-directed inhibitors (FAPI) as radiopharmaceuticals (4,5). FAP also shows strong expression in healthy endometrium and has been implicated in endometriosis lesions (6-9)....\nMethods and materials\nIn this retrospective study, nine premenopausal women with confirmed endometriosis (test group) and nine premenopausal women without known endometriosis (reference group) underwent PET/MRI or PET/CT with 68Ga-OncoFAP (now under development as 68Ga-BED003). 7 patients in the test group underwent PET/MRI, while 2 patients in the test group and all patients in the reference group underwent PET/CT. Standard MRI sequences were combined with PET and tracer uptake was assessed semi-quantitatively. Lesions were categorized based on a modified #ENZIAN segmentation. Clinical assessment or laparoscopy (when available) served...\nResults\nIn the test group, at least one endometriosis-related finding was identified in 6 of 7 patients who received PET/MRI when only MRI was evaluated, compared to all patients when combined PET/MRI was reviewed. In the test group, PET/MRI identified 45 of 91 segments (49.5%) as likely endometriotic compared with 17 of 91 segments (18.7%) with MRI alone. PET/CT and PET/MRI datasets showed focal tracer uptake in 44 of 108 segments (40.7%) in the test group, significantly higher than the 14 of 108 segments (13.0%) in...\nConclusion\nThese initial findings suggest that 68Ga-BED003 FAP-directed PET/MRI may improve the detection and characterization of endometriosis, particularly in anatomically challenging regions where conventional MRI is limited. As a potential adjunct to existing imaging strategies, 68Ga-BED003 FAP-PET/MRI may refine noninvasive assessment and guide personalized management of endometriosis. Larger prospective studies are warranted to validate these findings, establish standardized imaging protocols, and determine the diagnostic accuracy of this novel technique.\nPersonal information and conflict of interest\nJ. Brandt:\nNothing to disclose\nP. Backhaus:\nNothing to disclose\nD. Ventura:\nNothing to disclose\nS. Eltrop:\nNothing to disclose\nP. Schindler:\nNothing to disclose\nReferences\n1. Chapron C, Marcellin L, Borghese B, Santulli P. Rethinking mechanisms, diagnosis and management of endometriosis. Nat Rev Endocrinol. 2019;15:666-682.2. Pascoal E, Wessels JM, Aas-Eng MK, et al. Strengths and limitations of diagnostic tools for endometriosis and relevance in diagnostic test accuracy research. Ultrasound Obstet Gynecol. 2022;60:309-327.3. Maciel C, Ferreira H, Djokovic D, et al. MRI of endometriosis in correlation with the #Enzian classification: applicability and structured report. Insights Imaging. 2023;14:120.4. Backhaus P, Gierse F, Burg MC, et al. Translational imaging of the fibroblast activation...","source_license":"CC0","license_restricted":false}