Pitfalls in Pathology-Fibroepithelial Stromal Polyp of the Bladder

Abstract

Abstract Introduction/Objective The fibroepithelial stromal polyp is a benign polypoid proliferation of the stroma with overlying, usually squamous epithelium. It was originally reported in 1966 and is a generally recognized lesion of the female genital tract. Because the lesion contains atypical stromal cells, it can be mistaken for a sarcoma, particularly if it shows hypercellularity, pleomorphism, and atypical mitoses. It is often found in the female lower genital tract, urethra, and rarely extragenital sites, such as the breast. Other unusual locations such as the anus and nasal cavity have also been reported. The lesion is hormonally related and affects mostly reproductive-age women. Rare cases were reported in the male urinary tract and genital area. Because it is not well known in the bladder, overinterpretation as a sarcoma is possible. Methods/Case Report We report a ~60-year-old patient with a history of lower urinary tract symptoms due to prostatic hypertrophy on maximal medical therapy. He had been experiencing hematuria. On office cystoscopy, he was found to have a 3 cm prostate mildly obstructing the urethra, and 2 small velvety, erythematous patches on the posterior bladder wall. At cystoscopy, he was seen to have a small posterior bladder lesion, which was resected without difficulty. The pathology laboratory received two fragments of pink/tan soft tissue measuring 0.1 and 0.2 cm in the greatest dimension. On histology, the overlying urothelium was benign. The stroma was collagenous and hypocellular, containing scattered atypical and multinucleated cells, similar to the fibroepithelial stromal polyp well recognized in the female lower genital tract. Results (if a Case Study enter NA) N/A. Conclusion Benign fibroepithelial stromal polyp is an uncommon lesion usually seen in the lower genital tract of reproductive aged women. The presence in the bladder of a male is exceptionally rare. Recognition of the lesion will prevent overdiagnosis as a malignancy.