Aquino Suzanne L, Kuester Landon B, Muse Victorine V, Halpern Elkan F, Fischman Alan J
Department of Radiology, Massachusetts General Hospital, 55 Fruit Street, FND 202, Boston, MA, 02114, USA.
Eur J Nucl Med Mol Imaging. 2006 Jun;33(6):692-6. doi: 10.1007/s00259-005-0018-x. Epub 2006 Mar 3.
The purpose of this study was to determine the accuracy of detection of small pulmonary nodules on quiet breathing attenuation correction CT (CTAC) and FDG-PET when performing integrated PET/CT, as compared with a diagnostic inspiratory CT scan acquired in the same imaging session.
PET/CT scans of 107 patients with a history of carcinoma (54 male and 53 female, mean age 57.3 years) were analyzed. All patients received an integrated PET/CT scan including a CTAC acquired during quiet respiration and a contrast-enhanced CT acquired during inspiration in the same session. Breathing CTAC scans were reviewed by two thoracic radiologists for the presence of pulmonary nodules. FDG-PET scans were reviewed to determine accuracy of nodule detection. Diagnostic CT was used as the gold standard to confirm or refute the presence of nodules.
On the CTAC scans 200 nodules were detected, of which 183 were true positive (TP) and 17, false positive. There were 109 false negatives (FN). Overall, 51 (48%) patients had a false interpretation, including 19 in whom CT was interpreted as normal for lung nodules. The average size of the nodules missed was 3.8+/-2 mm (range 2-12 mm). None of the nodules missed on the CTAC scans were detected by PET. In the right lung there were 20 TP, 42 true negative (TN), 11 FP, and 34 FN interpretations with a sensitivity in nodule detection of 37% (CI 24-51%) and a specificity of 79% (CI 66-89%). In the left lungs there were 16 TP, 65 TN, 3 FP, and 23 FN interpretations, with a sensitivity of 41% (CI 26-58%) and a specificity of 96% (CI 88-99%).
The detection of small pulmonary nodules by breathing CTAC and FDG-PET is relatively poor. Therefore an additional diagnostic thoracic CT scan obtained during suspended inspiration is recommended for thorough evaluation of those patients in whom detection of pulmonary metastases is necessary for management.
本研究旨在确定在进行PET/CT检查时，与在同一成像环节中获取的诊断性吸气CT扫描相比，静息呼吸衰减校正CT（CTAC）和FDG-PET检测小肺结节的准确性。
对107例有癌症病史的患者（54例男性，53例女性，平均年龄57.3岁）的PET/CT扫描进行分析。所有患者均接受了一次PET/CT综合扫描，包括在静息呼吸时获取的CTAC以及在同一环节吸气时获取的增强CT。两名胸部放射科医生对呼吸CTAC扫描进行评估，以确定是否存在肺结节。对FDG-PET扫描进行评估，以确定结节检测的准确性。诊断性CT被用作确认或排除结节存在的金标准。
在CTAC扫描中检测到200个结节（其中183个为真阳性，17个为假阳性）。有109个假阴性。总体而言，51例（48%）患者存在假诊断，其中19例CT对肺结节的诊断被判定为正常。漏诊结节的平均大小为3.8±2mm（范围2-12mm）。PET未检测到CTAC扫描中漏诊的任何结节。在右肺，有20例假阳性、42例假阴性、11例假阳性和34例假阴性诊断，结节检测的敏感性为37%（可信区间24%-51%），特异性为79%（可信区间66%-89%）。在左肺，有16例假阳性、65例假阴性、3例假阳性和23例假阴性诊断；敏感性为41%（可信区间26%-58%），特异性为96%（可信区间88%-99%）。
通过呼吸CTAC和FDG-PET检测小肺结节的效果相对较差。因此，对于那些为了治疗需要检测肺转移的患者，建议在屏气吸气时额外进行一次诊断性胸部CT扫描，以进行全面评估。
