PURPOSE: The usefulness of fluorine 18 fluorodeoxyglucose ((18)F-FDG) imaging in differentiated thyroid cancer (DTC) has been demonstrated by investigators. The aim of this study is to compare the ability of fluorodeoxyglucose (FDG)-single photon emission computed tomography (SPECT) to detect metastatic DTC with posttherapeutic iodine131 ((131)I) scintigraphy. METHODS: 239 patients (78 men, 161 women; age range, 23-76 years, mean 45 years); All patients underwent FDG-SPECT and (131)I whole-body scan. RESULTS: The sensitivity of (18)F-FDG and (131)I imaging in the patients with high hTg levels is 48.7% (114/234) and 50.4% (118/234) respectively. However, the combined sensitivity of both protocols is 89.7% (210/234). In the patients with (131)I Imaging negative, the sensitivity of (18)F-FDG is 79.3%,but in the patients with (131)I imaging positive, the sensitivity of (18)F-FDG is only 18.6%. CONCLUSION: This study with (131)I and (18)F-FDG in FDG-SPECT further demonstrates the single study of (131)I whole body scan or (18)F-FDG imaging can not provide a high enough sensitivity for the detection of metastatic thyroid cancer. But, the combined protocols can get better results for the staging of thyroid carcinoma with the alternating uptake of (131)I and (18)F-FDG.
PURPOSE: The usefulness of fluorine 18 fluorodeoxyglucose ((18)F-FDG) imaging in differentiated thyroid cancer (DTC) has been demonstrated by investigators. The aim of this study is to compare the ability of fluorodeoxyglucose (FDG)-single photon emission computed tomography (SPECT) to detect metastatic DTC with posttherapeutic iodine131 ((131)I) scintigraphy. METHODS: 239 patients (78 men, 161 women; age range, 23-76 years, mean 45 years); All patients underwent FDG-SPECT and (131)I whole-body scan. RESULTS: The sensitivity of (18)F-FDG and (131)I imaging in the patients with high hTg levels is 48.7% (114/234) and 50.4% (118/234) respectively. However, the combined sensitivity of both protocols is 89.7% (210/234). In the patients with (131)I Imaging negative, the sensitivity of (18)F-FDG is 79.3%,but in the patients with (131)I imaging positive, the sensitivity of (18)F-FDG is only 18.6%. CONCLUSION: This study with (131)I and (18)F-FDG in FDG-SPECT further demonstrates the single study of (131)I whole body scan or (18)F-FDG imaging can not provide a high enough sensitivity for the detection of metastatic thyroid cancer. But, the combined protocols can get better results for the staging of thyroid carcinoma with the alternating uptake of (131)I and (18)F-FDG.