Table 1.

Cytological features associated with intravesical chemotherapy and low grade urothelial tumours

Feature	Thiotepa, mitomycin C	Low grade urothelial tumour
Cellularity	Early: high	Usually high
	Late: low
Cell size	Enlarged	Normal to minimal enlargement
Nuclear/cytoplasmic ratio	Normal	Increased
Staining	Hyperchromatic	Hyperchromatic
Nuclear borders	Irregular	Irregular
Chromatin	Fine, regular	Fine, regular
Nucleoli	Variable	Variable
Multinucleated cells and vacuolated cytoplasm	Common	Rare
Architecture	Loose, dyscohesive	Papillary and loose clusters
DNA ploidy	Diploid	Usually diploid