Urothelial dysplasia in random mucosal biopsies from patients with bladder tumours.

A prospective study of the incidence of urothelial dysplasia in random mucosal biopsies from cystoscopically normal appearing mucosa was carried out in 90 patients with bladder tumours at the initial diagnosis. More than 50% of invasive bladder tumours were accompanied by wide-spread urothelial dysplasia, in half of these cases characterized as carcinoma in situ supporting the idea that bladder cancer is a diffuse urothelial disease. Although suggesting an early radical treatment of invasive bladder cancer, such action should not be taken before a careful follow-up study of these patients have provided information on the natural history of diffuse urothelial dysplasia associated with bladder tumours.