PET/MR Outperforms PET/CT in Suspected Occult Tumors. (February 2017)

• Record Type: Journal Article
• Authors: Sekine, Tetsuro; Barbosa, Felipe de Galiza; Sah, Bert-Ram; Mader, Cäcilia E.; Delso, Gaspar; Burger, Irene A.; Stolzmann, Paul; ter Voert, Edwin E.; von Schulthess, Gustav K.; Veit-Haibach, Patrick; Huellner, Martin W.
• Is Part Of: Clinical nuclear medicine. Volume 42:Number 2(2017)
• Publication Date: 2017-02
• Subjects: PET/MR -- PET/CT -- oncology -- head and neck cancer -- multimodality imaging -- cancer of unknown primary -- occult tumors; Nuclear medicine -- Periodicals; Radioisotope scanning -- Periodicals; Nuclear Medicine -- Periodicals; 616.07575
• DOI: 10.1097/RLU.0000000000001461
• Languages: English
• ISSNs: 0363-9762

Abstract

Abstract : Background: To compare the diagnostic accuracy of PET/MR and PET/CT in patients with suspected occult primary tumors. Methods: This prospective study was approved by the institutional review board. Sequential PET/CT-MR was performed in 43 patients (22 male subjects; median age, 58 years; range, 20-86 years) referred for suspected occult primary tumors. Patients were assessed with PET/CT and PET/MR for the presence of a primary tumor, lymph node metastases, and distant metastases. Wilcoxon signed-rank test was performed to compare the diagnostic accuracy of PET/CT and PET/MR. Result: According to the standard of reference, a primary lesion was found in 14 patients. In 16 patients, the primary lesion remained occult. In the remaining 13 patients, lesions proved to be benign. PET/MR was superior to PET/CT for primary tumor detection (sensitivity/specificity, 0.85/0.97 vs 0.69/0.73; P = 0.020) and comparable to PET/CT for the detection of lymph node metastases (sensitivity/specificity, 0.93/1.00 vs 0.93/0.93; P = 0.157) and distant metastases (sensitivity/specificity, 1.00/0.97 vs 0.82/1.00; P = 0.564). PET/CT tended to misclassify physiologic FDG uptake as malignancy compared with PET/MR (8 patients vs 1 patient). Conclusions: PET/MR outperforms PET/CT in the workup of suspected occult malignancies. PET/MR may replace PET/CT to improve clinical workflow.