Clinical utility of ¹⁸F-FDG PET/CT in staging and treatment planning of urachal adenocarcinoma

Abstract

Purpose: Our objective was to evaluate the impact of utility of ¹⁸Fluorine (¹⁸F)-Fluorodeoxyglucose (FDG) positron emission tomography (PET) computed tomography (CT) in the management of urachal adenocarcinoma (UrC-ADC). Methods: A retrospective analysis of patients with UrC-ADC from 2001-2019 at Memorial Sloan Kettering was performed. Mayo stage prior to ¹⁸F-FDG-PET/CT, rates of detection of the primary malignancy and metastases on ¹⁸F-FDG PET/CT, Mayo stage after ¹⁸F-FDG-PET/CT, and changes in patient management were determined. Results: Of 21 patients with UrC-ADC prior to ¹⁸F-FDG-PET/CT, Mayo staging was I/II in 8, III in 3 and IV in 10. ¹⁸F-FDG-PET/CT detected previously unidentified metastases in 8 of 21 (38%) patients, resulting in upstaging of disease in 3 (14%) patients, and a change in treatment in 4 patients (19%). Conclusion: ¹⁸F-FDG PET/CT has clinical utility in patients with UrC-ADC by identifying metastatic disease not appreciated on anatomic imaging, leading to changes in staging and patient management.