Fibroepithelial Polyp of the Urinary Tract
Definition
- Benign urothelial polyp with both epithelial and stromal components
Diagnostic Criteria
- Usually a solitary lesion in bladder and urethra in adults, upper tract in children
- Generally scant inflammation and no associated cystitis
- Cystoscopic appearance is suggestive of papillary neoplasm rather than cystitis
- Polypoid lesion
- Projections range from club-like (clover leaf) to stubby or long
- Complex branching not prominent
- Projections range from club-like (clover leaf) to stubby or long
- Stroma more prominent than in urothelial neoplasms
- Typically fibrous, may have edematous areas
- May have atypical stromal fibroblasts
- Large hyperchromatic nuclei with smudgy chromatin
- Lined by normal urothelium
- Infrequent cases reported with columnar or mucinous areas
- No mitotic figures
- May contain florid cystitis cystica/glandularis
- May fill stroma leading to blunt club-like lobulated polyps
- Fusion of epithelial nests may simulate nested carcinoma
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342
Original posting/updates: 10/20/12