Detection of lung cancer with positron coincidence gamma camera using fluorodeoxyglucose in comparison with dedicated PET

Objective: Dual-head gamma cameras with sodium iodide(NaI) detectors operated in coincidence mode provide a new approach for imaging with positron-labeled tracers. The purpose of this study was to evaluaate the feasibility of FDG imaging with positron coincidence detection gamma camera(PCD) in detecting lung tumor in comparison with FDG imaging with the dedicated positron emission tomography(PET). Methods and maaterial: Twenty-six lesions of 13patients with suspected lung cancer were studied with both FDG PET and FDG PCD on the same day. Pulmonary lesions were analyzed visually and semi-quantitatively using the ratio of target-to-background counts(T/B ratio). Results and conclusions: FDG PCD and FDG PET could detect visually 21 lesions(80.8percent) and 23 lesions(88.0percent), respectively. The mean T/B ratio and standard deviation(S.D.) of FDG PCD was 4.6+/-3.9, significantly lower than that of FDG PET(11.4+/-6.6,P<0.001). When pulmonary lesions were no more than 2.0 cm in diameter,the sensitivity of FDG PCD was 37.5percent, significantly inferior to that of FDG PEt(62.5percent,P