Papillary Urothelial (Transitional Cell) Carcinoma
Definition
- Papillary urothelial neoplasms
Alternate/Historical Names
- The term Urothelial is preferred over Transitional as is is more specific and includes neoplasms with non-transitional differentiation arising in urothelium
- (Flat) urothelial carcinoma in situ is covered separately
Diagnostic Criteria
- Papillary urothelial lesions span a range from hyperplasia to high grade
carcinoma
- Papillary urothelial hyperplasia
- An essentially sessile, undulating lesion without well formed papillae
- Short stromal spikes but no thin fibrovascular cores
- Spikes usually no longer than the thickness of the epithelium
- Bland epithelium
- Thickness may be normal or increased
- Urothelial papilloma
- Infrequent branching of fibrovascular cores
- Infrequent fusing of papillae
- Epithelial lining is identical to normal urothelium
- Normal thickness (4-6 cells)
- No atypia
- No nucleoli
- Orderly maturation
- Intact umbrella cell layer
- No mitotic figures
- Infrequent branching of fibrovascular cores
- Papillary urothelial neoplasm of low malignant potential (PUNLUMP)
- Occasional branching of fibrovascular cores
- Occasional fusing of papillae
- Epithelial lining is identical to normal urothelium but increased in thickness
- Normal thickness is 4-6 cells
- Atypia
absent to minimal
- Nuclei normal size to slightly enlarged but uniform
- Nucleoli absent or inconspicuous
- Orderly maturation
- Intact umbrella cell layer
- Rare to no mitotic figures
- No invasion
- Occasional branching of fibrovascular cores
- Low grade papillary urothelial carcinoma
- Frequent branching of fibrovascular cores
- Frequent fusing of papillae
- Lining epithelium is predominantly orderly with only mild abnormalities in maturation and polarity
- Epithelial cells only mildly atypical
- Uniform slight enlargement
- Nucleoli generally inconspicuous
- If present they should be small and uniform without other high grade features
- Scattered hyperchromatic cells may be present
- Umbrella cells usually present
- Occasional mitotic figures may be present
- No atypical figures
- Foci with high grade features may be present but make up <5% of the tumor
- Frequent branching of fibrovascular cores
- High grade papillary urothelial carcinoma
- Frequent branching of fibrovascular cores
- Frequent fusing of papillae
- Lining epithelium is disordered, lacking maturation and polarity
- Umbrella cells usually absent
- Frequent epithelial cells are markedly atypical
- Moderate to marked nuclear hyperchromatism and pleomorphism
- Nucleoli prominent and multiple
- Frequent mitotic figures
- May be atypical
- May be poorly cohesive
- High grade features make up ≥5% of the tumor
- Frequent branching of fibrovascular cores
- Variant patterns are described separately
- Chordoid
- Microcystic
- Micropapillary
- Nested
- Plasmacytoid
- Sarcomatoid
- Papillary urothelial hyperplasia
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342
Original posting/updates: 10/20/12, 12/29/12
