Bertolotto Michele, Cicero Calogero, Catalano Orlando, Currò Francesca, Derchi Lorenzo Egildo
Department of Radiology, University of Trieste, Trieste, Italy.
Department of Radiology, San Bassiano Hospital, Bassano del Grappa, Italy.
J Ultrasound Med. 2018 Jan;37(1):233-242. doi: 10.1002/jum.14335. Epub 2017 Jul 29.
To estimate the prevalence of solid renal tumors isoenhancing to kidneys in all vascular phases on contrast-enhanced sonography and to investigate whether they can be differentiated from pseudomasses.
A computer search of the databases of 3 institutions identified 31 patients with pseudomasses and 380 patients with solid tumors investigated with contrast-enhanced sonography. Nineteen of 380 (5%) patients had tumors isoenhancing in all phases. Images and clips of these 19 tumors and the 31 pseudomasses were blindly assessed by 2 radiologists. They were asked to differentiate tumors from pseudomasses based on echogenicity, vascular architecture, and the presence of the medulla.
Isoenhancing tumors were clear cell carcinomas (n = 7), angiomyolipomas (n = 3), papillary tumors (n = 3), metastasis (n = 1), and oncocytoma (n = 1). In the 4 nonoperated tumors, the diagnosis was confirmed by progression during the follow-up. There were 3 markedly hyperechoic, 11 mildly hypo/hyperechoic, and 5 isoechoic masses. Most pseudomasses were isoechoic to kidneys (23 of 31), with the medulla identified in 22 of 31 and 15 of 31 by radiologists 1 and 2, respectively. One and 2 pseudomasses were considered tumors by radiologists 1 and 2, respectively. One isoechoic isoenhancing tumor was not identified on contrast-enhanced sonography. Isoenhancing tumors in all phases were differentiated from pseudomasses by combining grayscale and contrast-enhanced sonography (areas under the receiver operating characteristic curve, 0.997 for reader 1; 0.969 for reader 2), with very good inter-reader agreement (weighted κ = 0.81).
In our retrospective study, 5% of solid renal lesions were isoenhancing to kidneys in all phases. Differentiation from pseudomasses was possible by looking at baseline sonographic features and vascular characteristics.
评估在超声造影所有血管期与肾脏等增强的实性肾肿瘤的患病率，并研究其是否能与假瘤相鉴别。
通过计算机检索3家机构的数据库，确定了31例患有假瘤的患者和380例接受超声造影检查的实性肿瘤患者。380例患者中有19例（5%）的肿瘤在各期均表现为等增强。这19个肿瘤和31个假瘤的图像及片段由2名放射科医生进行盲法评估。要求他们根据回声、血管结构和髓质的存在情况将肿瘤与假瘤区分开来。
等增强肿瘤包括透明细胞癌（n = 7）、血管平滑肌脂肪瘤（n = 3）、乳头状肿瘤（n = 3）、转移瘤（n = 1）和嗜酸细胞瘤（n = 1）。在4例未手术的肿瘤中，随访期间病情进展证实了诊断。有3个明显高回声、11个轻度低/高回声和5个等回声肿块。大多数假瘤与肾脏等回声（31例中的23例），放射科医生1和2分别在31例中的22例和31例中的15例中识别出髓质。放射科医生1和2分别将1个和2个假瘤误诊为肿瘤。1个等回声等增强肿瘤在超声造影上未被识别。通过结合灰阶超声和超声造影，各期等增强肿瘤与假瘤得以区分（受试者工作特征曲线下面积，读者1为0.997；读者2为0.969），读者间一致性非常好（加权κ = 0.81）。
在我们的回顾性研究中，5%的实性肾病变在各期均与肾脏等增强。通过观察基线超声特征和血管特征可以将其与假瘤区分开来。
