Tubulovillous adenoma of the urinary bladder

We report a case of vesical tubulovillous adenoma that occurred in a backgr ound of protracted chronic cystitis with intestinal-type glandular metaplas ia and extensive cellular atypia (dysplasia) in the hat mucosa. Flow cytome try analysis showed DNA aneuploidy in the adenoma. Increased expression of the tumor suppresser gene, p53, and also of cellular proliferation markers (proliferating cell nuclear antigen and MIB-1) were detected in the villous adenoma and in the dysplastic regions of the fiat metaplastic mucosa. Thes e findings provide insight into the biology of intestinal metaplasia and al so lend support to the theory of the chronic irritation-metaplasia-dysplasi a-carcinoma sequence.