Thallium and FDG uptake by atelectasis with bronchogenic carcinoma

We report a case of bronchogenic carcinoma with atelectasis studied by T1-S PECT and FDG-PET. In the carcinoma, abnormally high uptake of T1 and FDG we re detected, but in the region of atelectasis, an abnormally high uptake of T1 with a relatively low uptake of FDG were observed. On quantitative anal yses, the T1 retention indexes of the tumor and atelectasis were 29.7 and 4 2.0. The mean SUVs of FDG of the tumor and the atelectasis were 8.92 and 1. 28. T1-SPECT could not distinguish the atelectasis from the carcinoma. FDG- PET was superior to T1-SPECT in this case in detecting malignancy and disti nguishing it from atelectasis.