Diagnostic value of combined 18 F-FDG PET/CT and HRCT for minimally invasive pulmonary adenocarcinoma

PENG Liao-he; HU Xiao-yan; ZHOU Xuan; QIU Da-sheng; LI Jie

Abstract：Objective To evaluate the diagnostic value of combined 18 F-FDG PET/CT and HRCT for minimally invasive adenocarcinoma(MIA) .Methods The 18F-FDG PET/CT images of 28 cases with pathologically confirmed MIA were studied .All were followed up by HRCT study .The morphological and radioactive findings of the lesions were reviewed , and the maximum standard uptake values (SUVmax) were measured .The diagnostic accuracy of PET/CT ,HRCT ,and combined PET/CT and HRCT were analyzed .The synergistic effect of combined PET/CT and HRCT were investigated . Results 18 F-FDG PET imaging showed local abnormal radioactive uptake in 19 of 28 cases .When SUVmax of 2 .5 was employed as criteria in the diagnosis of MIA ,the sensitivity of 18 F-FDG PET imaging was 32 .1% .Of the total of 28 ca-ses ,10 had ground glass opacity (GGO) changes ,17 exhibited mixed nodules with GGO changes around the lesions ,and 1 case presented with solid nodules .HRCT showed that the lesions were showing lobulation in 18 cases (64 .3% ) ,spicu-lation in 20 cases (71 .4% ) ,vacuolar changes or air bronchogram in 21 cases (75% ) ,pleural indentation in 12 cases (42.9% ) ,vascular convergence in 10 cases (35 .7% ) ,and round nodule in 13 cases (46 .4% ) .The diagnostic accuracy of PET/CT ,HRCT ,and combined PET/CT and HRCT for MIA was 71 .4% ,82 .1% and 96 .4% respectively .Conclusion The false negative rate and the misdiagnosis rate were high in the diagnosis of MIA with routine PET /CT imaging .Combi-ning 18 F-FDG PET/CT with HRCT was reasonable and practicable ,which had synergistic effect in diagnosing MIA and could greatly improve the diagnostic accuracy .