Invest Radiol 2021 Mar 25. Epub 2021 Mar 25.
From The Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, and Department of Radiology, Xinhua Hospital, affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China Department of Radiology, Division of Abdominal Imaging, Massachusetts General Hospital, Boston IRCCS, Department of Radiology, The Institute for Hospitalization and Healthcare (IRCCS) SDN, Napoli, Italy Division of Nuclear Medicine, Department of Radiology, Faculdade de Ciências Médicas, Universidade Estadual de Campinas (Unicamp), Campinas, São Paulo, Brazil The Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston Department of Surgery, Massachusetts General Hospital, Boston Department of Medicine, Massachusetts General Hospital, Boston The Institute for Hospitalization and Healthcare (IRCCS) SDN, Napoli, Italy Department of Radiology and Nuclear Medicine, University Suor Orsola Benincasa and SDN IRCCS, Napoli, Italy Department of Radiology and Nuclear Medicine, Assuta Medical Center and School of Medicine, Tel Aviv University, TLV, Israel Department of Nuclear Medicine, The Chaim Sheba Medical Center Tel Hashomer Israel Departamento de Medicina Nuclear, HM Hospitales, Madrid, Spain Institute of Diagnostic and Interventional Radiology, University Hospital Essen, University Duisburg-Essen, Essen, Germany Department of Radiology and Nuclear Medicine, Massachusetts General Hospital, Boston, MA.
Objective: The aim of this study was to compare the performance of positron emission tomography (PET)/magnetic resonance (MR) versus stand-alone PET and stand-alone magnetic resonance imaging (MRI) in the detection and characterization of suspected liver metastases.
Materials And Methods: This multi-institutional retrospective performance study was approved by the institutional review boards and was Health Insurance Portability and Accountability Act compliant, with waiver of informed consent. Seventy-nine patients with confirmed solid extrahepatic malignancies who underwent upper abdominal PET/MR between February 2017 and June 2018 were included. Where focal hepatic lesions were identified, the likelihood of a diagnosis of a liver metastasis was defined on an ordinal scale for MRI, PET, and PET/MRI by 3 readers: 1 nuclear medicine physician and 2 radiologists. The number of lesions per patient, lesion size, and involved hepatic segments were recorded. Proof of metastases was based on histopathologic correlation or clinical/imaging follow-up. Diagnostic performance was assessed using sensitivity, specificity, positive and negative predictive values, and receiver operator characteristic curve analysis.
Results: A total of 79 patients (53 years, interquartile range, 50-68; 43 men) were included. PET/MR had a sensitivity of 95%, specificity of 97%, positive predictive value of 97%, and negative predictive value of 95%. The sensitivity, specificity, positive predictive value, and negative predictive value of MRI were 88%, 98%, 98%, and 90% and for PET were 83%, 97%, 97%, and 86%, respectively. The areas under the curve for PET/MRI, MRI, and PET were 95%, 92%, and 92%, respectively.
Conclusions: Contrast-enhanced PET/MR has a higher sensitivity and negative predictive value than either PET or MRI alone in the setting of suspected liver metastases. Fewer lesions were characterized as indeterminate by PET/MR in comparison with PET and MRI. This superior performance could potentially impact treatment and management decisions for patients with suspected liver metastases.