RT Journal Article SR Electronic T1 Integrated PET/CT in Differentiated Thyroid Cancer: Diagnostic Accuracy and Impact on Patient Management JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 616 OP 624 VO 47 IS 4 A1 Holger Palmedo A1 Jan Bucerius A1 Alexius Joe A1 Holger Strunk A1 Niclas Hortling A1 Susanne Meyka A1 Roland Roedel A1 Martin Wolff A1 Eva Wardelmann A1 Hans-Juergen Biersack A1 Ursula Jaeger YR 2006 UL http://jnm.snmjournals.org/content/47/4/616.abstract AB The aim of this study was to investigate the diagnostic accuracy and impact on patient management of the new integrated PET/CT modality in patients with suspected iodine-negative, differentiated thyroid carcinoma (DTC). Methods: Forty patients with DTC and a suggestion of iodine-negative tumor tissue underwent PET/CT examination (370 MBq 18F-FDG, coregistered PET/CT whole-body images). As the first step of analysis, PET and CT images were scored blindly and independently by 2 nuclear medicine physicians and 2 radiologists. A 5-point scale was used. The second step consisted of a consensus reading, during which a virtual side-by-side fusion of PET and CT images was initially evaluated and afterward the “real” fusion (i.e., coregistered) PET/CT images were also scored with the same 5-point scale. The imaging results were compared with histopathologic findings and the course of disease during further follow-up examinations. Results: One hundred twenty-seven lesions in 40 patients were evaluated. Diagnostic accuracy was 93% and 78% for PET/CT and PET, respectively (P = 0.049, per-patient analysis). In 17 (74%) of 23 patients with suspicious 18F-FDG foci, integrated PET/CT added relevant information to the side-by-side interpretation of PET and CT images by precisely localizing the lesion(s). In tumor-positive PET patients, PET/CT fusion by coregistration led to a change of therapy in 10 (48%) patients. Futile surgery was prevented in an additional 3 patients. Conclusion: Integrated PET/CT is able to improve diagnostic accuracy in a therapeutically relevant way in patients with iodine-negative DTC. By precisely localizing tumor tissue, image fusion by integrated PET/CT is clearly superior to side-by-side interpretation of PET and CT images.