Sonographic patterns of renal cell carcinoma with emphasis on relation to tumor size.

The sonographic appearance of 37 renal cell carcinomas was reviewed with particular emphasis on the relationship between the echo pattern of tumor and tumor size. Small carcinomas tended to be solid and hypoechoic; seven lesions less than 5 cm in the largest dimension were either hypo- or isoechoic . The echogenicity level of the solid parts within the lesion, whether it was solid or mixed, tended to increase as the tumor grew. It is important to recognize that the sonographic appearance of renal cell carcinomas varies with the size of the tumor.