Abstract:
Objective To investigate the features and diagnostic values of 18F-FDG PET and high resolution CT(HRCT) in patients with bronchial alveolar carcinoma(BAC).
Methods Seventeen cases with pathologically confirmed BAC and 1 case confirmed inflammation were studied retrospectively.The standardized uptake value(SUV) of the lesions were detected and 18F-FDG uptake characteristics were studied.The diagnostic values of 18F-FDG PET, HRCT and 18F-FDG PET combined with HRCT were analyzed.
Results ① In the group of solitary nodule(n=5), SUV of lesions were 1.5-3.5.HRCT(4/5) demonstrated spiculated(4/4), lobulated(3/4), pleural indentation(3/4), vascular convergence(3/4), vacuole sign(2/4) and ground-glass sign(1/4).②In the group of lobar consolidation(n=6), SUV of lesions were 1.6-2.3. HRCT(5/6) demonstrated ground-glass(5/5), pleural indentation(3/5), vacuole sign(2/5), air bronchogram sign (2/5) and blood vessel convergency(1/5).③In the group of mixed shadow(n=4), SUV of lesions were 4.5-10.0.Ground-glass sign, vacuole sign, pleural tag and air bronchogram sign were seen in 2, 1, 2 and 3 cases respectively.④There was 1 case in the group of mass lesion.The SUV of lesion was 5.6, and HRCT demonstrated lobulated, cavity, pleural indentation and blood vessel convergency.⑤There was 1 case in the multi-nodular group, SUV was 4.6, lobulation and spiculation sign were found.⑥SUV was 1.2 in the false positive case, with the lesion size of 2.1 cm×2.3 cm.
Conclusions Low uptake of 18F-FDG in solitary nodule and lobar consolidation groups might cause false negative in the diagnosis of BAC.To improve the diagnosisaccuracy and to decrease misdiagnosis rate of BAC, combination of HRCT with 18F-FDG PET should be carried out.