Transitional cell carcinoma of urinary bladder
- Tumor occurs from the mucosa of the urinary bladder.
- It is composed of a large number of branched papillae, covered with multilayered epithelium, often with anastomoses.
- They are built up of tender fibro vascular ‘core’, covered with atypical urinary epithelium, which thickness exceeds several times the normal one.
- On the surface are found so called ‘umbrella’ cells.
- More differentiated forms have soft papillae and faint cell atypia.
- In tumor progression are found abnormal mitoses and infiltration in the bladder’s wall. Papillae are short, thick and at some places are fused together.