It is essential to examine the preliminary film of an IVU carefully,because even large calculi can be completely hidden within the opacified collecting system once contrast medium has been given Renal simple cyst 10 At last 25%of people over 50 years have renal cysts the si do not communicate with the collecting system Most arise in the renal cortex IVU finds Renal Pelvis and Calices be compressed CT manifestation 10: Intemal homogeneous attenuation of near water density Lack of measurable thickness of the cyst wall Lack of contrast enhancement Smooth interface with the renal parenchyma 10 MR manifestation ●Round or ovoid lesion ·Intemal homo ogeneous conten 。wihsgnalchaactericssimiartourme:lowsgnalntcnsyonTIWM. high signal on T2WI Nearly imperceptible wall thickness Lack of contrast enhancement Smooth interface with the renal parenchyma Renal cell carcinoma 15 Outline:Renal cell carcinoma (RCC)is the most common renal tumor, comprising approximately 85%of all primary malignant renal neoplasms Renal tumors are usually solitary Histologically:the most common type of malignant renal cell cancer is clear cell adenocarcinoma RCCs are relatively slow growing and may be large before they produce RCC can metastasize by lymphatic and haematogenous routes⚫ It is essential to examine the preliminary film of an IVU carefully, because even large calculi can be completely hidden within the opacified collecting system once contrast medium has been given Renal simple cyst ⚫ At least 25% of people over 50 years have renal cysts ⚫ the size and frequency of cysts increase with age ⚫ contain clear serous fluid ⚫ do not communicate with the collecting system ⚫ Most arise in the renal cortex IVU finds ⚫ Renal Pelvis and Calices be compressed CT manifestation ⚫ Round or ovoid lesion ⚫ Internal homogeneous attenuation of near water density ⚫ Lack of measurable thickness of the cyst wall ⚫ Lack of contrast enhancement ⚫ Smooth interface with the renal parenchyma MR manifestation ⚫ Round or ovoid lesion ⚫ Internal homogeneous content ⚫ with signal characteristics similar to urine ：low signal intensity on T1WI， high signal on T2WI ⚫ Nearly imperceptible wall thickness ⚫ Lack of contrast enhancement ⚫ Smooth interface with the renal parenchyma Renal cell carcinoma ⚫ Outline:Renal cell carcinoma (RCC) is the most common renal tumor, comprising approximately 85% of all primary malignant renal neoplasms ⚫ Renal tumors are usually solitary ⚫ Histologically: the most common type of malignant renal cell cancer is clear cell adenocarcinoma ⚫ RCCs are relatively slow growing and may be large before they produce symptoms ⚫ RCC may be locally aggressive ⚫ RCC can metastasize by lymphatic and haematogenous routes 10’ 10’ 10’ 15’