超声造影检出微小肾细胞癌的策略探讨

The strategy for improving the detection of minute renal cell carcinoma with contrast-enhanced ultrasonography

目的:探讨超声造影(contrast-enhanced ultrasonography,CEUS)检出最大径(超声测值)≤15 mm的微小肾细胞癌(minute renal cell carcinoma,MRCC)的应用价值及策略。方法:分析2007年11月至2019年10月于复旦大学附属中山医院行超声造影检查且经手术病理证实的53例MRCC患者的临床和影像资料,观察病灶常规超声及CEUS的声像图表现。常规超声观察肾肿瘤的大小、部位、回声、形态、边界及有无彩色血流信号。CEUS主要观察占位有无增强、增强减退表现及病灶内部灌注和均匀度。结果:手术后病理证实透明细胞癌48例,乳头状癌4例,嫌色细胞癌1例。常规超声发现肿瘤完全位于肾内12个,余均稍凸向肾外;位于背侧的肿块10个,显示非常困难,需要仔细对照CT/MRI才能发现。常规超声显示MRCC多为实质高回声肿块,边界清或欠清,部分可伴有囊性成分,多数伴有不同丰富程度的血流信号。CEUS时MRCC主要表现为皮质期同步增强、达峰值呈富血供、实质期快速消退为主。比较MRCC常规超声和CEUS的表现,两者在肿块边界、血供和均匀度方面的差异均有统计学意义(χ 2=12.425、20.247、7.185,均 P<0.01)。 结论:CEUS能明显提高MRCC的检出率,优于常规超声。

Objective To investigate the value of contrast-enhanced ultrasonography(CEUS)in detecting minute renal cell carcinoma(MRCC)smaller than 15 mm(by ultrasonic measurement)and the strategy to improve its detection rate.Methods Fifty-three pathologically confirmed MRCCs by surgery from November 2007 to October 2019 at Zhongshan Hospital of Fudan University were enrolled in this retrospectively study.All of them underwent both conventional ultrasound and CEUS examinations.The clinical and imaging data were collected and analyzed.Common features,such as tumor size,location,echogenicity,morphology,border,and blood flow signals were observed on conventional ultrasound.On CEUS,the presence of enhancement,wash in and wash out pattern,perfusion uniformity within the lesions were observed.Results Post-operative pathology confirmed 48 clear cell carcinomas,4 papillary carcinomas,and 1 chromophobe cell carcinoma.On conventional ultrasound,12/53 lesions showed no protrusion out of the kidney,and 41/53 cases slightly protruded out of the kidney.There was considerable difficulty in the detection of ten lesions,which was achieved with the guidance of CT/MRI,due to their dorsal location of the kidney.On conventional ultrasound,solid,hyper-echoic,color flow signal with varying degrees were the main features of MRCC.The boundary could be well-or ill-defined,and cystic changes existed in part of cases.On CEUS,most MRCCs showed simultaneous enhancement in cortical phase,iso-to hyper-enhancement at peak,and rapid washout in parenchymal phase.The comparisons of imaging features demonstrated that the characteristics were significantly different between conventional ultrasound and CEUS with regard to boundaries,blood supply,and perfusion uniformity(χ2=12.425,20.247,7.185;all P<0.01).Conclusions CEUS can significantly improve the detection rate of MRCC,which is superior to conventional ultrasound.