"One-stop-shop" staging: should we prefer FDG-PET/CT or MRI for the detection of bone metastases?
OBJECTIVE
The aim of this study was to compare the diagnostic accuracy of fully diagnostic, contrast-enhanced whole-body FDG-PET/CT and whole-body MRI for detection of bone metastases in patients suffering from newly diagnosed non-small cell lung cancer and malignant melanoma.


METHODS
109 consecutive non-small cell lung cancer (n=54) and malignant melanoma (n=55) patients underwent whole-body FDG-PET/CT and whole-body MRI for initial tumor staging. All images were evaluated by four experienced physicians (three radiologists, one nuclear medicine physician). The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for detection of bone metastases were determined for both modalities. Statistically significant differences between FDG-PET/CT and MRI were calculated with Fisher's Exact test (p<0.05). Clinical and imaging follow-up data with a mean follow-up time of 434 days served as the reference standard.


RESULTS
According to the reference standard 11 patients (10%) suffered from bone metastases. The sensitivity, specificity, PPV, NPV, and accuracy for the detection of osseous metastases was 45%, 99%, 83%, 94%, and 94% with whole-body FDG-PET/CT and 64%, 94%, 54%, 96%, and 91% with whole-body MRI. The difference was not statistically significant (p=0.6147).


CONCLUSIONS
FDG-PET/CT and MRI seem to be equally suitable for the detection of skeletal metastases in patients suffering from newly diagnosed non-small cell lung cancer and malignant melanoma. Both modalities go along with a substantial rate of false-negative findings requiring a close follow-up of patients who are staged free of bone metastases at initial staging.
Heusner
Till
T
Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, University at Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany.
Gölitz
Philipp
P
Hamami
Monia
M
Eberhardt
Wilfried
W
Esser
Stefan
S
Forsting
Michael
M
Bockisch
Andreas
A
Antoch
Gerald
G
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001859:Bone Neoplasms / Q000175:diagnosis* / Q000556:secondary*; D002289:Carcinoma, Non-Small-Cell Lung; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008545:Melanoma / Q000175:diagnosis* / Q000556:secondary*; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012878:Skin Neoplasms / Q000175:diagnosis; D014057:Tomography, X-Ray Computed / Q000379:methods*
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18