Caiyuan Zhang1, Aileen O'Shea2, Chiara Anna Parente3, Barbara Juarez Amorim4, Peter Caravan5, Christina R Ferrone6, Lawrence S Blaszkowsky7, Andrea Soricelli8, Marco Salvatore9, David Groshar10, Hanna Bernstine10, Liran Domachevsky11, Lina Garcia Canamaque12, Lale Umutlu13, Herrmann Ken13, Ciprian Catana5, Umar Mahmood14, Onofrio Antonio Catalano. 1. 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. 2. Department of Radiology, Division of Abdominal Imaging, Massachusetts General Hospital, Boston. 3. IRCCS, Department of Radiology, The Institute for Hospitalization and Healthcare (IRCCS) SDN, Napoli, Italy. 4. Division of Nuclear Medicine, Department of Radiology, Faculdade de Ciências Médicas, Universidade Estadual de Campinas (Unicamp), Campinas, São Paulo, Brazil. 5. The Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston. 6. Department of Surgery, Massachusetts General Hospital, Boston. 7. Department of Medicine, Massachusetts General Hospital, Boston. 8. The Institute for Hospitalization and Healthcare (IRCCS) SDN, Napoli, Italy. 9. Department of Radiology and Nuclear Medicine, University Suor Orsola Benincasa and SDN IRCCS, Napoli, Italy. 10. Department of Radiology and Nuclear Medicine, Assuta Medical Center and School of Medicine, Tel Aviv University, TLV, Israel. 11. Department of Nuclear Medicine, The Chaim Sheba Medical Center Tel Hashomer Israel. 12. Departamento de Medicina Nuclear, HM Hospitales, Madrid, Spain. 13. Institute of Diagnostic and Interventional Radiology, University Hospital Essen, University Duisburg-Essen, Essen, Germany. 14. Department of Radiology and Nuclear Medicine, Massachusetts General Hospital, Boston, MA.
Abstract
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.
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.