ABSTRACT
Cardiac uptake of 2-[(18)F]-fluoro-2-deoxy-d-glucose (FDG) is frequently observed on FDG positron-emission tomography combined with computed tomography (PET-CT) performed for diagnosis, staging, and assessment of therapeutic response of lymphoma and solid cancers, despite careful patient preparation to limit myocardial glucose substrate utilisation. We illustrate the varied physiological patterns of cardiac FDG uptake, and show a spectrum of pathological conditions causing FDG uptake within myocardial and pericardial structures, due to clinically important benign and malignant diseases. Recognition and awareness of these various causes of FDG uptake in the heart, along with the appropriate use of correlative contrast-enhanced CT and magnetic resonance imaging (MRI) will facilitate correct interpretation.
Subject(s)
Fluorodeoxyglucose F18/pharmacokinetics , Heart Diseases/metabolism , Multimodal Imaging , Myocardium/metabolism , Pericardium/metabolism , Positron-Emission Tomography , Radiopharmaceuticals/pharmacokinetics , Tomography, X-Ray Computed , Adipose Tissue, Brown/metabolism , Artifacts , Cardiomyopathies/metabolism , Heart Atria/metabolism , Heart Ventricles/metabolism , Humans , Leukemia/metabolism , Lymphoma/metabolism , Organ Specificity , Papillary Muscles/metabolism , Pericarditis/metabolism , Sarcoidosis/metabolismABSTRACT
BACKGROUND: Positron emission tomography (PET) is more accurate than computed tomography (CT) in staging and restaging of lymphoma, but both are considered necessary. Increasingly, PET is carried out with a low-dose CT scan. Many patients undergo both PET/CT and standard diagnostic CT. The clinical utility of performing both studies in patients with lymphoma was evaluated. PATIENTS AND METHODS: Patients with lymphoma who underwent concurrent PET/CT and diagnostic CT (a scan pair) were identified, and findings detected in either scan but not both were documented. Discrepancies were considered significant if they were related to either lymphoma or another disease process which potentially required intervention. RESULTS: Eighty-seven scan pairs were identified. PET/CT detected additional lesions over diagnostic CT in 30 patients, of which 11 demonstrated increased clinical stage. Lymphoma therapy changed based on PET/CT in two patients, and one occult rectal cancer was detected. In contrast, diagnostic CT detected five relevant findings, including two incidental findings (venous thrombosis) and three patients with splenic lesions, none of which could be confirmed as lymphoma. No patient had change of stage or lymphoma therapy based on diagnostic CT. CONCLUSION: In our series, diagnostic CT did not add value to staging or restaging of lymphoma when carried out concurrently with PET/CT.