What are the other Names for this Condition? (Also known as/Synonyms)

• Transitional Cell Papilloma
• Urothelial Papilloma of the Bladder
• Urothelial Papilloma of the Urinary Bladder

What is Urothelial Papilloma? (Definition/Background Information)

• Urothelial Papilloma is an uncommon and benign subtype of noninvasive lesion of the urothelium (the urothelial cells that line the urothelial tract). It is a solitary lesion that is commonly found around the urinary bladder (trigone region), and occasionally in the ureter
• The incidence of Urothelial Papilloma is less than 4% of all non-invasive urothelial tumors. Children and adults (age range 8-87 years) are known to present the tumor, but the incidence is higher between ages 40 and 50 years. A greater number of cases are observed in males than females
• The exact cause of formation of Urothelial Papilloma is presently not well-understood; the tumor is known to occur sporadically. Mutations involving the KRAS or HRAS genes are commonly observed in almost all cases
• Urothelial Papilloma is diagnosed under a microscope, on examination of the tumor cells by a pathologist. It is known to frequently mimic other neoplasms, such as fibroepithelial polyp, papillary urothelial neoplasm of low malignant potential, polypoid cystitis, and urothelial carcinoma. Hence, it is important to exclude these tumors prior to a definitive diagnosis
• The diagnosis of Urothelial Papilloma in individuals who have a past medical history of non-muscle invasive bladder cancer is challenging. In such cases, molecular studies may help determine whether there is recurrence of previously diagnosed malignancy. This diagnostic challenge is often encountered in superficially invasive urothelial carcinomas (non-muscle-invasive bladder cancer)
• The signs and symptoms of Urothelial Papilloma may not be significantly seen but can include painless hematuria (blood in urine) and the presence of a mass lesion that frequently ranges in size from 20-30 mm. The rate of recurrence following surgery is low, and occasional progression to a higher grade tumor is reported (observed in less than 1% of the cases)
• A surgical removal of Urothelial Papilloma via transurethral resection of bladder tumor (TURBT) is often curative. The prognosis is generally excellent as the tumor has a benign clinical course. However, regular follow-ups may be recommended due to a low risk for recurrence