动态增强CT和MRI诊断乳头状肾细胞癌

目的:探讨乳头状肾细胞癌的影像学表现、生物学行为、血液动力学特征、病理等及其相关关系,以提高诊断准确性。方法:经手术病理证实的乳头状肾细胞癌患者13例,术前行CT平扫及皮髄交界期和实质期增强扫描,注射流率3～4ml/s,2例同时行MRI检查。回顾性分析其CT和MRI表现并与手术病理结果进行对照。结果:13例中肿瘤位于右侧5例,左侧8例;呈圆形或椭圆形7例,分叶结节状或不规则形6例,其中呈边缘结节状突起5例、不规则形1例;直径1.5～9.0cm,平均4.7cm;肿瘤密度均匀4例,不均匀9例,所有肿瘤境界清楚。肿瘤平扫CT值18.3～35.9HU,平均26.3HU;动态增强皮髓交界期CT值27.9～57.1HU,平均36.2HU;实质期CT值34.8～71.0HU,平均48.6HU。实质期肿瘤境界最清楚,坏死囊变区不强化。2例行MRI检查,T1WI示肿瘤呈低～中等信号,T2WI呈等～低信号,MR动态增强特点与CT相似。结论:乳头状肾细胞癌的影像学表现有一定特征性,动态CT扫描和MRI对诊断和鉴别诊断有重要价值。

Dynamic Spiral CT and MR Findings of Papillary type Renal Cell Carcinoma

Objective:To study the imaging findings,biology and hemo-dynamic manifestations as well as pathology of papillary type renal cell carcinoma and to evaluate their correlationship,in order to improve the accuracy of diagnosis.Methods:13 cases with papillary type renal cell carcinoma confirmed by surgery and pathology underwent pre-and post-contrast (cortico-medullary phase and parenchymal phase) spiral CT before surgery.The injection rate of contrast medium was 3~4ml/s.Two patients had MR scanning simultaneously.The CT and MR findings were analyzed retrospectively and correlated with surgery and pathology.Results:Of the 13 patients,the tumor located in the right kidney (n=5),left kidney (n=8).7 masses were round or oval and 6 were irregular (n=1) or lobulated (n=5) in shape.The mean diameter of tumor was 4.7cm (ranged from 1.5 to 9.0cm).4 masses showed homogeneous and 9 masses showed heterogeneous attenuation.All of the tumor mass were well-defined.The CT value of the plain scans,corticomedullary phase and nephrographic phases was 18.3~35.9HU (mean,26.3HU),27.9~57.1HU (mean,36.2HU) and 34.8~71.0HU (mean,48.6HU) respectively.The margin of tumor mass was shown most clearly discernible in parenchymal phase,and the necrotic area within the mass didn't enhanced after contrast injection.The tumor presented hypo-to iso-intensity on SE T1WI and iso-to hypo-intensity on T2WI.Conclusion:Papillary type renal cell carcinoma showed certain imaging characteristics,dynamic CT and MRI provided important information in the diagnosis and differential diagnosis.