F-18-2-Fluoro-2-Deoxyglucose Positron Emission Tomography Compared to Technetium-99m Hexakis-2-Methoxyisobutyl Isonitrile Single Photon Emission Chest Tomography in the Diagnosis of Indeterminate Lung Lesions

Background:18FDG-PET plays a significant role in diagnosing malignancy of lung lesions but remains an expensive test available at a limited number of sites in Italy. Objective: We prospectively compare the diagnostic accuracy of 99mTc-MIBI- SPECT and 18FDG-PET in patients with indeterminate lung lesions to demonstrate that 99mTc-MIBI-SPECT may be considered as a valid alternative when 18FDG-PET is not available. Methods: 52 patients with indeterminate lung lesion were examined by 18FDG-PET and 99mTc-MIBI-SPECT before surgery. The scintigraphic findings were analyzed visually and semiquantitatively and then correlated to the definitive diagnosis. Results: 38 were malignant lesions while 14 were benign. At visual analysis, the sensitivities of 18FDG-PET and 99mTc-MIBI-SPECT were 92 and 84%, respectively (McNemar test p = 0.4), whereas the specificities were 78.6 and of 93% (p = 1.0), respectively. At semiquantitative analysis, 18FDG-PET showed a sensitivity and specificity of 92 and 71.4%, respectively, while 99mTc-MIBI-SPECT produced a sensitivity and specificity of 86 and 100%, respectively (p = 0.194). For lymph node staging, 18FDG-PET and 99mTc-MIBI-SPECT have a sensitivity and specificity of 88 and 92 of 77 and 100%, respectively. Conclusion:99mTc-MIBI-SPECT is similar to 18FDG-PET in the detection of lung malignancies and represents an alternative when PET is not available. Yet, the combination of both techniques may improve patient selection for surgery.