Primary staging with 2[18F]-FDG-PET/CT and -PET/MRI and radiotherapy response evaluation with MRI in uterine cervical cancer: an interim analysis of a prospective clinical trial.

Background: In uterine cervical cancer (UCC), tumour staging is performed according to the 2018 International Federation of Gynecology and Obstetrics (FIGO) system, where imaging is incorporated, or the more generic Tumour Node Metastasis (TNM) classification. With the technical development in diagnostic imaging, continuous prospective evaluation of the different imaging methods contributing to stage determination is warranted. The aims of this interim study were to (1) evaluate the performance of radiological FIGO (rFIGO) and T staging (rT) with 2-fluorine-18-fluoro-deoxy-glucose (2[18F]-FDG)-positron emission tomography with computed tomography (PET/CT) and with magnetic resonance imaging (PET/MRI), compared to clinical FIGO (cFIGO) and T (cT) staging based on clinical examination and conventional imaging, in treatment-naïve UCC, and to (2) identify possible MRI biomarkers for early treatment response after radiotherapy.