title: Whole-Body18F-FDG PET/CT Is Superior to CT as First-Line Diagnostic Imaging in Patients Referred with Serious Nonspecific Symptoms or Signs of Cancer: A Randomized Prospective Study of 200 Patients.
abstract: A fast-track pathway has been established in Denmark to investigate patients with serious nonspecific symptoms and signs of cancer (NSSC), who are not eligible to enter an organ-specific cancer program. The prevalence of cancer in this cohort is approximately 20%. The optimal screening strategy in patients with NSSC remains unknown. The aim of the study was to investigate whether18F-FDG PET/CT was superior to CT as an initial imaging modality in patients with NSSC. In a randomized prospective trial, the imaging modalities were compared with regard to diagnostic performance.Methods:Two hundred patients were randomized 1:1 to whole-body18F-FDG PET/CT or CT of the thorax and abdomen as the imaging modality. A tentative diagnosis was established after first-line imaging. The final referral diagnosis was adjudicated by the physician, when sufficient data were available.Results:One hundred ninety-seven patients were available for analysis because 3 patients withdrew consent before scanning. Thirty-nine (20%) patients were diagnosed with cancer, 10 (5%) with an infection, 15 (8%) with an autoimmune disease, and 76 (39%) with other diseases. In the remaining 57 patients (28%), no specific disease was found.18F-FDG PET/CT had a higher specificity (96% vs. 85%;P= 0.028) and a higher accuracy (94% vs. 82%;P= 0.017) than CT. However, there were no statistically significant differences in sensitivity (83% vs. 70%) or negative predictive values (96% vs. 92%). No difference in days to final referral diagnosis according to randomization group could be shown (7.2 vs. 7.6 d). However, for the subgroups in which the imaging modality showed a suggestion of malignancy, there was a significant delay to final diagnosis in the CT group compared with the18F-FDG PET/CT group (11.6 vs. 5.7 d;P= 0.02).Conclusion:Compared with CT, we found a higher diagnostic specificity and accuracy of18F-FDG PET/CT for detecting cancer in patients with NSSC.18F-FDG PET/CT should therefore be considered as first-line imaging in this group of patients.
authors.affiliation: Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark.
authors.forename: Anne-Mette
authors.initials: AM
authors.lastname: Lebech
authors.affiliation: Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark.
authors.forename: Anne
authors.initials: A
authors.lastname: Gaardsting
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Rigshospitalet and University of Copenhagen, Copenhagen, Denmark.
authors.forename: Annika
authors.initials: A
authors.lastname: Loft
authors.affiliation: Department of Clinical Physiology & Nuclear Medicine, Copenhagen University Hospital, Hvidovre, Denmark; and.
authors.forename: Jesper
authors.initials: J
authors.lastname: Graff
authors.affiliation: Department of Radiology, Copenhagen University Hospital, Hvidovre, Denmark.
authors.forename: Elena
authors.initials: E
authors.lastname: Markova
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Rigshospitalet and University of Copenhagen, Copenhagen, Denmark.
authors.forename: Anne Kiil
authors.initials: AK
authors.lastname: Bertelsen
authors.affiliation: Department of Clinical Physiology & Nuclear Medicine, Copenhagen University Hospital, Hvidovre, Denmark; and.
authors.forename: Jan Lysgård
authors.initials: JL
authors.lastname: Madsen
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Rigshospitalet and University of Copenhagen, Copenhagen, Denmark.
authors.forename: Kim Francis
authors.initials: KF
authors.lastname: Andersen
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Rigshospitalet and University of Copenhagen, Copenhagen, Denmark.
authors.forename: Eric von
authors.initials: EV
authors.lastname: Benzon
authors.affiliation: Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark.
authors.forename: Morten
authors.initials: M
authors.lastname: Helms
authors.affiliation: Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark.
authors.forename: Lars R
authors.initials: LR
authors.lastname: Mathiesen
authors.affiliation: Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark.
authors.forename: Kim P
authors.initials: KP
authors.lastname: David
authors.affiliation: Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre, Denmark.
authors.forename: Gitte
authors.initials: G
authors.lastname: Kronborg
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Rigshospitalet and University of Copenhagen, Copenhagen, Denmark akjaer@sund.ku.dk.
authors.forename: Andreas
authors.initials: A
authors.lastname: Kjaer
mesh_terms: D003718:Denmark / Q000453:epidemiology; D055088:Early Detection of Cancer / Q000379:methods / Q000706:statistics & numerical data*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D009369:Neoplasms / Q000000981:diagnostic imaging* / Q000453:epidemiology; D015588:Observer Variation; D000072078:Positron Emission Tomography Computed Tomography / Q000379:methods / Q000706:statistics & numerical data*; D015995:Prevalence; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity; D063189:Symptom Assessment; D014057:Tomography, X-Ray Computed / Q000379:methods*; D051598:Whole Body Imaging / Q000379:methods / Q000706:statistics & numerical data*
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: FDG-PET/CT; cancer; molecular imaging; prospective study; randomized study