Pilot Study of [18F] Fluorodeoxyglucose Positron Emission Tomography (FDG-PET)/Magnetic Resonance Imaging (MRI) for Staging of Muscle-invasive Bladder Cancer (MIBC).

Computed tomography (CT) has limited diagnostic accuracy for staging of muscle-invasive bladder cancer (MIBC). [18F] Fluorodeoxyglucose positron emission tomography (FDG-PET)/magnetic resonance imaging (MRI) is a novel imaging modality incorporating functional imaging with improved soft tissue characterization. This pilot study evaluated the use of preoperative FDG-PET/MRI for staging of MIBC.

Twenty-one patients with MIBC with planned radical cystectomy were enrolled. Two teams of radiologists reviewed FDG-PET/MRI scans to determine: (1) presence of primary bladder tumor; and (2) lymph node involvement and distant metastases. FDG-PET/MRI was compared with cystectomy pathology and computed tomography (CT).

Eighteen patients were included in the final analysis, most (72.2%) of whom received neoadjuvant chemotherapy. Final pathology revealed 10 (56%) patients with muscle invasion and only 3 (17%) patients with lymph node involvement. Clustered analysis of FDG-PET/MRI radiology team reads revealed a sensitivity of 0.80 and a specificity of 0.56 for detection of the primary tumor with a sensitivity of 0 and a specificity of 1.00 for detection of lymph node involvement when compared with cystectomy pathology. CT imaging demonstrated similar rates in evaluation of the primary tumor (sensitivity, 0.91; specificity, 0.43) and lymph node involvement (sensitivity, 0; specificity, 0.93) when compared with pathology.

This pilot single-institution experience of FDG-PET/MRI for preoperative staging of MIBC performed similar to CT for the detection of the primary tumor; however, the determination of lymph node status was limited by few patients with true pathologic lymph node involvement. Further studies are needed to evaluate the potential role for FDG-PET/MRI in the staging of MIBC.

Clinical genitourinary cancer. 2020 Mar 05 [Epub ahead of print]

Patrick J Eulitt, Ersan Altun, Arif Sheikh, Terence Z Wong, Michael E Woods, Tracy L Rose, Eric M Wallen, Raj S Pruthi, Angela B Smith, Matthew E Nielsen, Young E Whang, William Y Kim, Paul A Godley, Ethan M Basch, Grace U David, Juanita Ramirez, Allison M Deal, W Kimryn Rathmell, Ronald C Chen, Marc A Bjurlin, Weili Lin, Joseph K Lee, Matthew I Milowsky

Division of Hematology/Oncology, Department of Medicine, University of North Carolina School of Medicine, Chapel Hill, NC., Division of Abdominal Imaging, Department of Radiology, University of North Carolina School of Medicine, Chapel Hill, NC., Division of Nuclear Medicine, Department of Diagnostic, Molecular, and Interventional Radiology, Icahn School of Medicine at Mount Sinai, New York, NY., Division of Nuclear Medicine, Department of Radiology, Duke University School of Medicine, Durham, NC., Department of Urology, Loyola University Chicago Stritch School of Medicine, Chicago, IL., Division of Hematology/Oncology, Department of Medicine, University of North Carolina School of Medicine, Chapel Hill, NC; Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC., Department of Urology, University of North Carolina School of Medicine, Chapel Hill, NC., Department of Radiation Oncology, University of North Carolina School of Medicine, Chapel Hill, NC., Biomedical Research Imaging Center, University of North Carolina School of Medicine, Chapel Hill, NC., Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC., Division of Hematology/Oncology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN., Division of Abdominal Imaging, Department of Radiology, University of North Carolina School of Medicine, Chapel Hill, NC; Department of Diagnostic Imaging, National University Hospital of Singapore, Singapore., Division of Hematology/Oncology, Department of Medicine, University of North Carolina School of Medicine, Chapel Hill, NC; Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC. Electronic address: .