Monarch Disease Ontology term MONDO_0006474 (transitional cell carcinoma) is a malignant neoplasm arising from the transitional epithelium, usually affecting the urinary bladder, ureter, or renal pelvis. It may or may not have a papillary configuration. It is graded 1 to 3 or 4 according to the degree of cellular differentiation and architectural patterns. Grade 1 transitional cell carcinoma is histologically benign but it may recur. Transitional cell carcinomas may also affect the upper respiratory tract and the ovaries. Also known as: carcinoma of transitional epithelial cell, carcinoma of urothelial cell, carcinoma, urothelial, malignant, transitional carcinoma, transitional epithelial cell carcinoma, urothelial cell carcinoma.