肾黏液样小管状和梭形细胞癌的影像学表现初探

Imaging manifestations of mucinous tubular and spindle cell carcinoma of the kindey ： a pilot study

目的 探讨肾黏液样小管状和梭形细胞癌（mucinous tubular and spindle cell carcinoma of the kindey,MTSCC-K）的影像学特点. 方法 回顾性分析2010年11月至2014年11月5例经病理证实的MTSCC-K患者的影像学资料.5例均行CT检查,其中4例同时接受常规MR、弥散加权成像（diffusion weighted imaging,DWI）检查,测量增强前、后（皮质期、实质期）肿瘤的CT值与MR信号强度及肿瘤与正常肾皮质的表观弥散系数（apparent diffusion coefficient,ADC）值,计算肿瘤MR强化率. 结果 5例MTSCC-K位于右肾2例,左肾3例;最大径3.2～7.1 cm;5例均为类圆形;4例有假包膜;5例边界清楚;3例有坏死囊变;1例有钙化;5例均无出血及脂肪,无周围侵犯.平扫：CT呈等密度或等、低密度,T1WI以等信号或等、高信号为主,T2WI呈等信号或低、等、高混杂信号;增强：呈轻度均匀或不均匀强化;实性成分DWI图呈高信号、ADC图呈低信号.平扫、皮质期及实质期肿瘤平均CT值分别为32.6、46.5、66.5 HU,肿瘤与正常肾皮质的平均ADC值分别为1.23×10^-3、2.31×10^-3 mm^2/s,皮质期、实质期肿瘤平均MR强化率分别为32.7％、104.9％. 结论 MTSCC-K的影像学特点为形态规则,有假包膜,边界清楚,部分有坏死囊变及钙化,无周围侵犯,恶性征象少,平扫CT呈等密度或等、低密度,T1WI以等信号或等、高信号为主,动态增强呈轻度渐进性强化,具有一定的特征性.

Objective To investigate the imaging characteristics of mucinous tubular and spindle cell carcinoma of the kindey （MTSCC-K）.Methods Five cases of pathologically confirmed MTSCC-K were analyzed retrospectively.All patients underwent CT scanning,and 4 cases underwent conventional MR and diffusion weighted imaging （DWI） scanning.MR enhancement ratio for the tumor was calculated according to MR signal intensity of pre-and post-contrast in tumor and apparent diffusion coefficient （ADC） values of tumor and normal renal cortical.Results Two case located in the right kindey,and 3 cases located in the left kindey.The maximum diameter of lesions ranged from 3.2 cm to 7.1 cm.Five cases showed nearly round shape with clear borderline.Pseudocapsule was found in 4 cases,3 cases had necrosis and cystic,and 1 case had calcification.There were no hemorrhage,fat and invasion of adjacent tissue.Isodensity or hypodense tumors were found on plain CT.Isointense or hyperintense tumors were found on plain T1WI,while isointense or mixed-signal tumors were found on plain T2WI.Slightly homogeneous or heterogeneous enhancement was observed on dynamic enhanced CT or MR,and the solid component of tumors showed hyperintense on DWI and hypointense on ADC.The mean CT value of tumor at the plain,cortical and nephrographic phase was 32.6 HU,46.5 HU and 66.5 HU,respectively.The mean ADC value of tumor and normal renal cortical was 1.23 × 10^-3 mm^2/s and 2.31 × 10^-3 mm^2/s,respectively.The mean MR percentage of enhancement value of tumor was 32.7% and 104.9%,respectively.Conclusions The imaging characteristics of MTSCC-K include nearly round shape,pseudocapsule,clear borderline,necrosis,cystic and calcification.There is no invasion of adjacent tissue and seldom malignant appearances.Isodensity or hypodense can be observed on plain CT,isointense or hyperintense on plain T1WI,and a mild continuously enhancement on dynamic enhanced scanning.