History and CT imaging
A 54-year-old man with incidental CT finding.
54岁男性，CT偶然发现病变。
Shown below are axial CT images through the kidneys. In order: unenhanced, arterial phase, and portal venous phase.
平扫：
动脉期：
门脉期：
1.Where is the salient abnormality located?
病变在哪里？
Liver
Pancreas
Kidney
Colon
MR axial images through the level of the kidneys are shown below in the following sequences:
T2WI FSE
T2WI FSE 脂肪抑制
T1WI 同相位(echo time = 4.6 msec)
T1WI 反相位 (echo time = 2.3 msec)
DWI
ADC图
MR平扫
动脉期
门脉期：
平衡期
2.The right renal lesion restricts diffusion.
右肾病变弥散受限
True
False
3.There is invasion of the renal sinus fat.
病变侵犯肾窦脂肪
True
False
4.There is fat within the renal lesion.
病变内含有脂质成分
True
False
5.The renal lesion is T1 hyperintense to renal parenchyma.肾脏内病灶相对于肾实质呈T1WI高信号。
True
False
6，What is the most likely diagnosis?
Hyperdense cyst 高密度肾囊肿
Lymphoma 淋巴瘤
Angiomyolipoma 血管平滑肌脂肪瘤
Papillary renal cell carcinoma 乳头状肾癌
Clear cell renal cell carcinoma 透明细胞肾癌
选择题答案：
-
Kidney
-
True
-
False
-
False
-
False
-
Papilary renal cell carcinoma
-
An exophytic hyperdense lesion is seen in the upper pole of the right kidney.
右肾上极高密度结节，突向肾外。
-
Lesion demonstrates enhancement on arterial and portal venous phases.
增强扫描动脉期及静脉期可见病灶强化。
MRI:
-
An exophytic enhancing lesion is seen in the upper pole of the right kidney corresponding to hyperdense CT mass.
与CT对应，可见右肾上极肿块，向肾外生长。
-
T1 and T2 hypointense relative to kidney.
T1WI和T2WI上，病灶相对于肾脏呈略低信号。
-
Restricts diffusion.
弥散受限。
-
No fat within the lesion, demonstrated on chemical shift imaging.
病灶内无脂质成分，可见化学位移位移。
-
No invasion of subjacent renal sinus fat.
病灶没有侵犯邻近肾窦脂肪。
-
Transitional cell carcinoma: Centrally located, poorly defined, peripherally dilated calyces.
移行细胞癌：位置一般更靠近肾脏内部，边界不清，邻近肾盏扩张。
-
Angiomyolipoma: Detection of macroscopic fat.
血管平滑肌脂肪瘤：病灶内可见脂肪成分
-
Oncocytoma: Cannot establish a definitive diagnosis and most require biopsy or surgery.
嗜酸细胞瘤：单纯通过影像很难确诊，需要结合病理或手术明确诊断。
-
Primary lymphoma: Usually large retroperitoneal mass than engulfs the kidney.
原发性淋巴瘤：腹膜后肿块，通常体积较大，包绕肾脏。
-
Secondary lymphoma: Hematogenous metastases to the kidneys in patients with known prior treated lymphoma. Multiple bilateral homogenous hypodense and hypoenhancing lesions are characteristic.
继发性淋巴瘤：其他部位淋巴瘤血行转移至肾脏。典型表现为双肾多发均匀稍低密度病灶，增强后略强化。
Papillary renal cell carcinoma
乳头状肾细胞癌
-
Clear cell: Most common subtype = 75% of renal cell carcinomas in most series
肾透明细胞癌：最常见的类型，约占肾细胞癌的75%。
-
Papillary: Second most common subtype
乳头状肾细胞癌：第二常见亚型。
-
Chromophobe 肾嫌色细胞癌
-
Collecting duct 肾集合管癌
-
Unclassified 未分类肾细胞癌
Imaging Findings for Specific Subtypes
Clear cell RCC 肾透明细胞癌:
-
Tend to have greater enhancement and more heterogeneity.
通常更加不均匀，增强扫描强化更明显
-
Termed clear cell by pathologists secondary to intracellular lipid and glycogen; the former can be detected by loss of signal intensity on opposed phase images when compared with corresponding in phase images.
病理科医师将细胞内脂质和糖原称为透明细胞，病灶内的脂质成分可以通过MR同反相位上的信号衰减检测出来。
Papillary cell RCC 乳头状肾细胞癌：
-
Enhances less than clear cell carcinoma.
强化低于肾透明细胞癌
-
No lipid on chemical shift imaging.
化学位移成像示病灶内没有脂质成分
-
Restricts diffusion to a greater degree than clear cell carcinoma.
相对于肾透明细胞癌，弥散受限更明显。
-
Lower T2-weighted signal intensity than clear cell renal carcinoma
T2WI信号低于肾透明细胞癌。