Proliferation and ultrastructure of papillary transitional cell carcinoma of the human bladder

The ultrastructure of human bladder epithelium and bladder tumors has been examined with particular reference to the organization of well-differentiated papillary carcinoma. Estimates of the potential growth rates of the tumors have been obtained, using the colcemid stathmokinetic technique. The relation of cell organization to rates of division is discussed. Tumors of low malignancy have many of the ultrastructural features of normal epithelium; invasive tumors have a more simple cytoplasm with loss of specialization of the surface cells' unit membrane and suppression of telolysosome formation.