Correct answer: C

Histology: Polypoid fragments of tissue lined by normal urothelium and underlying clusters of urothelial nests and prostatic glands surrounded by loose bland cellular stroma.

Discussion: Fibroepithelial polyps (FEPs) of the urinary tract are rare with most cases reported in children. Clinical symptoms were hematuria, urinary urgency, and hesitancy, all related to lower urinary tract obstruction. Most lesions are located near the verumontanum or the bladder neck. Histologically, they are lined by normal-appearing urothelium. There are three architectural patterns. The most common pattern (seen in this case) consists of a polypoid mass with club-like projections resembling a cloverleaf with florid cystitis cystica et glandularis. The second pattern consists of a papillary tumor composed of numerous small, rounded fibrovascular cores containing dense fibrous tissue. The last morphologic pattern consists of a polypoid lesion with secondary tall finger-like projections. FEPs lack prominent edema and inflammation seen in polypoid cystitis and contain broader stalks with dense fibrous tissue, in contrast to the thin delicate loose fibroconnective tissue seen in the stalk of papillomas. Occasionally, some lesions may contained atypical degenerative-appearing stromal cells. Because FEPs in adults are rare, some of these cases can be misdiagnosed as urothelial neoplasms or reactive conditions. Recognition of the precise histologic features can facilitate its correct diagnosis.

Reference:
1. Tsuzuki T, Epstein JI. Fibroepithelial polyp of the lower urinary tract in adults. Am J Surg Pathol. 2005 Apr;29(4):460-6.