Transitional Cell Carcinoma, Urinary Tract, Mouse

Abstract

Transitional cell carcinomas may be single or multiple and can occur in the urinary bladder, urethra, ureter, and the renal pelvis, all of which are lined with transitional epithelium. The wall of the unopened urinary bladder may appear to be thick, solid, and opaque; in the distended bladder the wall may be mostly transparent, but with localized, white opaque areas (Wood and Bonser 1979). In the opened urinary bladder, transitional cell carcinomas usually appear in the vertex or fundus as solid nodular white/brown or hemorrhagic masses with a smooth or irregular surface (Frith et al. 1980; Wood and Bonser 1979). Some transitional cell carcinomas of the urinary bladder may have a papillary appearance with a slender stalk of attachment: others may be more sessile and have a broader base of attachment. The tumors may vary in size from barely visible to those that fill the bladder lumen, resulting in hydroureter and hydronephrosis in some cases (Wood and Bonser 1979). Transitional cell carcinomas of the ureter and urethra are usually not visible grossly in the mouse. In the renal pelvis, transitional cell carcinomas occur as white/yellow nodular enlargements and grossly cannot be distinguished from renal cell carcinomas.