Effect of hyperthermic vesical irrigation with bleomycin on the ultrastructure of the well-differentiated tumour and non-tumorous mucosa of the human urinary bladder.

Bladder tumours and non-tumorous bladder mucosa were studied by scanning and transmission electron microscopy in seven patients who had undergone hyperthermic vesical irrigation with bleomycin. The treatment induced sloughing of the outermost tumour cells, an increase of blebs and a decrease of cytoplasmic processes of the deeply located tumour cells as well as cellular degeneration. Although less severe, non-tumorous mucosa showed similar changes. Microvilli also appeared on the superficial cells of non-tumorous mucosa after the treatment. This treatment is effective by inducing cell degeneration and desquamation but not selective to the bladder tumour.