Department of Radiology, Yantai Yuhuangding Hospital, Qingdao University School of Medicine, Yantai, China
Department of Pathology, Yantai Yuhuangding Hospital, Qingdao University School of Medicine, Yantai, China
Diagn Interv Radiol. 2023 Mar 29;29(2):205-211. doi: 10.5152/dir.2022.21834. Epub 2023 Jan 27.
To explore the utility of four-phase computed tomography (CT) in distinguishing renal oncocytoma with central hypodense areas from clear cell renal cell carcinoma (ccRCC).
Eighteen patients with oncocytoma and 63 patients with ccRCC presenting with central hypodense areas were included in this study. All patients underwent four-phase CT imaging including the excretory phases later than 20 min after contrast injection. Two blinded experienced radiologists visually reviewed the enhancement features of the central hypodense areas in the excretory phase images and selected the area demonstrating the greatest degree of enhancement of the tumor in the corticomedullary phase images. Regions of interest (ROIs) were placed in the same location in each of the three contrast-enhanced imaging phases. Additionally, ROIs were placed in the adjacent normal renal cortex for normalization. The ratio of the lesion to cortex attenuation (L/C) for the three contrast-enhanced imaging phases and absolute de-enhancement were calculated. The receiver operating characteristic curve was used to obtain the cut-off values.
Complete enhancement inversion of the central areas was observed in 12 oncocytomas (66.67%) and 16 ccRCCs (25.40%) ( = 0.003). Complete enhancement inversion combined with L/C in the corticomedullary phase lower than 1.0 ( < 0.001) or absolute de-enhancement lower than 42.5 HU ( < 0.001) provided 86.42% and 85.19% accuracy, 61.11% and 55.56% sensitivity, 93.65% and 93.65% specificity, 73.33% and 71.43% positive predictive value (PPV), and 89.39% and 88.06% negative predictive value (NPV), respectively, for the diagnosis of oncocytomas. Combined with complete enhancement inversion, L/C in the corticomedullary phase lower than 1.0 and absolute de-enhancement lower than 42.5 HU provided 87.65%, 55.56%, 96.83%, 83.33%, and 88.41% of accuracy, sensitivity, specificity, PPV, and NPV, respectively, for the diagnosis of oncocytomas.
The combination of enhancement features of the central hypodense areas and the peripheral tumor parenchyma can help distinguish oncocytoma with central hypodense areas from ccRCC.
探讨四期 CT 扫描在鉴别中央低密度区的肾嗜酸细胞瘤与透明细胞肾细胞癌（ccRCC）中的作用。
本研究纳入了 18 例嗜酸细胞瘤患者和 63 例中央低密度区 ccRCC 患者。所有患者均接受四期 CT 扫描，包括对比剂注射后 20 分钟以上的排泄期。两名有经验的放射科医生对排泄期图像中央低密度区的增强特征进行了盲法评估，并选择皮质髓质期图像中肿瘤增强最明显的区域。在每个增强期图像中，在相同位置放置感兴趣区（ROI）。此外，在相邻的正常肾皮质中放置 ROI 进行归一化。计算三个增强期图像的病变与皮质衰减比（L/C）和绝对减退值。使用受试者工作特征曲线获得截断值。
12 例嗜酸细胞瘤（66.67%）和 16 例 ccRCC（25.40%）出现完全增强反转（ = 0.003）。完全增强反转联合皮质髓质期 L/C 比值低于 1.0（ < 0.001）或绝对减退值低于 42.5 HU（ < 0.001）时，诊断嗜酸细胞瘤的准确率、敏感度、特异度、阳性预测值（PPV）和阴性预测值（NPV）分别为 86.42%、61.11%、93.65%、73.33%和 89.39%；85.19%、65.56%、93.65%、81.43%和 88.06%。完全增强反转联合皮质髓质期 L/C 比值低于 1.0 和绝对减退值低于 42.5 HU 时，诊断嗜酸细胞瘤的准确率、敏感度、特异度、PPV 和 NPV 分别为 87.65%、55.56%、96.83%、83.33%和 88.41%。
中央低密度区的强化特征与外周肿瘤实质相结合，有助于鉴别中央低密度区的嗜酸细胞瘤与 ccRCC。
