Purpose: Preoperatively differentiating uterine sarcomas from leiomyomas remains challenging using routine imaging. We evaluated whether quantitative venous-phase CT metrics, such as attenuation profiling and dual-energy CT (DECT) iodine mapping, can aid in discrimination. Methods: In this retrospective single-center study, cases of women with histopathologyproven leiomyoma or uterine sarcoma who underwent contrast-enhanced abdominopelvic CT (01/2010-01/2025) were included; lesions with dominant macrocalcifications were excluded. J o u r n a l P r e -p r o o fJournal Pre-proof On venous-phase CT, ROI-based HU profiles were computed on the slice showing the maximal cross-sectional area of each lesion; the leading profile-derived parameters were the intralesional minimum HU, maximal HU, and the HU (HU=max-min). Reader-consensus values were analyzed. In a DECT subset of 20 cases, readers placed lesion and aortic ROIs to compute normalized iodine concentration (NIC=iodineₗesion/iodineₐorta). Results: 81 patients were analyzed (leiomyoma n=41, sarcoma n=40; sarcoma subtypes: LMS n=15, MMMT/CS n=10, ESS n=9, adenosarcoma n=3, and UUS n=3). Sarcomas showed lower minimum HU and higher HU than leiomyomas (all p<0. 001), yielding AUC=0. 75 (minimum HU) and AUC=0. 73 (HU). DECT with normalized iodine concentration (NIC) was available in n=20 (10/10) and was higher in sarcomas, achieving AUC=0. 96 (Youden=0. 733, sensitivity=0. 80, specificity=1. 00). Reliability was good-toexcellent for HU features (ICC=0. 86-0. 97) and excellent for iodine metrics (ICC=0. 99-1. 00). Conclusion: Simple, aorta-normalized CT metrics may capture biologically plausible differences between uterine leiomyomas and sarcomas. In particular, aorta-normalized attenuation features showed fair discriminatory performance in the overall cohort, while DECT-derived NIC showed promising but exploratory performance in a small spectral subset that requires external confirmation.
Prucker et al. (Wed,) studied this question.