Metastatic bladder cancer is an aggressive disease that can often be difficult to diagnose and stage with conventional cross-sectional imaging. The primary objective of this study was to determine the clinical value of fluorine-18 2-fluoro-2-deoxy-D-glucose (18F-FDG) PET/MRI for surveillance and restaging of patients with muscle-invasive, locally advanced, and metastatic bladder cancer compared to conventional imaging methods.
This retrospective study enrolled patients with muscle-invasive, locally advanced and metastatic bladder cancer in a single institute evaluated with 18F-FDG PET/MRI. All patients also underwent conventional imaging with CT. Additional imaging may also have included 18F-FDG PET/CT (18F-FDG PET), or sodium fluoride (NaF) PET/CT in some patients. Images were reviewed by a diagnostic radiologist/nuclear medicine physician. Number of lesions and sites of disease were captured and compared between 18F-FDG PET/MRI and conventional imaging. Lesions were confirmed by sequential imaging or lesion biopsy. All patients were followed for survival.
Fifteen patients (4 for surveillance; 11 for restaging) underwent 34 18F-FDG PET/MRI scans. Each patient received a corresponding conventional CT around the time of the 18F-FDG PET/MRI (median 6 days). The 15 patients (11 male; 4 female) had a median age of 61.5 years (range 37-73) and histologies of urothelial carcinoma (n = 13) and small-cell carcinoma of the bladder (n = 2) diagnosed as stage 4 (n = 13), stage 3 (n = 1), or stage 2 (n = 1). 18F-FDG PET/MRI detected 82 metastatic malignant lesions involving lymph nodes (n = 22), liver (n = 10), lung (n = 34), soft tissue (n = 12), adrenal glands (n = 1), prostate (n = 1), and bone (n = 2) with a resultant advantage of 36% for lesion visibility in comparison with CT. Serial imaging or biopsy confirmed these lesions as malignant.
18F-FDG PET/MRI can detect metastatic lesions which cannot be identified on conventional CT, and this can allow for better treatment planning and improved disease monitoring during therapy.
Urologic oncology. 2021 Jun 16 [Epub]
Ali Cahid Civelek, Scot A Niglio, Ashkan A Malayeri, Jeffrey Lin, Sandeep Gurram, Heather J Chalfin, Baris Turkbey, Vladimir Valera, Seth M Steinberg, Andrea B Apolo
Radiology and Imaging Sciences Department, Nuclear Medicine Division, National Institutes of Health, Bethesda, MD., Genitourinary Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD., Radiology and Imaging Sciences Department, Nuclear Medicine Division, National Institutes of Health, Bethesda, MD; Genitourinary Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD., Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD., Biostatistics and Data Management Section, Office of the Clinical Director, National Cancer Institute, Rockville, MD., Genitourinary Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD. Electronic address: .