UROTHELIAL PAPILLOMA
- it is benign exophytic urothelial neoplasm accounting for 1% -4% of bladder tumors and characterized by non-branching papillary fronds lined by normal appearing urothelium
- The most common clinical presentation is hematuria.
- Microscopic features
- Papillary fronds are lined by normal appearing urothelium lacking atypia
- Rarely branching occurs but without fusion
- Most papillomas have slender fibrovascular stalks
- Superficial umbrella cells are often prominent with vacuolization of the cytoplasm and eosinophilic change. Variation occur from inconspicuous to cuboidal cells with slightly enlarged nuclei and paler cytoplasm to hobnail cells with abundant eosinophilic cytoplasm .
- Urothelial atypia other than that in umbrella cells, excludes the diagnosis of papilloma
- Mitosis are rare or absent and if present they are basal in location and not abnormal
Papilloma with prominent umbrella cells having abundant eosinophilic cytoplasm. Mild atypia is noted in the umbrella cells (H&E,X100)
Papillae lined by transitional epithelium of normal thickness and prominent umbrella cells (H&E,X100).
Papillae lined by transitional epithelium of normal thickness and prominent umbrella cells (H&E,X400).
Papillae lined by transitional epithelium of normal thickness and prominent umbrella cells (H&E,X400).
Papillae lined by transitional epithelium of normal thickness and prominent umbrella cells having vacuolated and eosinophilic cytoplasm (H&E,X400)