Renal and urinary tract masses: Pathology review

Renal and urinary tract masses are abnormal growths that can develop in the kidneys, ureters, bladder, and urethra. These masses may be either cysts or tumors. Renal cysts on ultrasounds appear to be tiny sacs filled with black fluid. Cysts can be either simple or complex when they have septations within. Renal tumors can be benign, like renal oncocytoma, or malignant, like renal cell carcinoma. Common urinary tract tumors include: Renal cell carcinoma: the most common type of renal cancer. It develops in the renal tubules and can metastasize to surrounding tissue. Transitional cell carcinoma: develops in the urothelial cells lining the urinary tract. Wilms' tumor: a rare type of kidney cancer typically affecting children.