[Precancerous importance of chronic cystitis and papilloma of the bladder].

Analyzes the findings of histologic studies of biopsies of a pathologically changed and visually intact bladder mucosa from 334 patients with chronic cystitis with nonproliferative, proliferative, and metaplastic changes (n = 164), papillomas (n = 62), and carcinomas (n = 108). Demonstrates the relationships between these conditions and their evolution over a follow-up of 36-72 months. Outlines the most typical patterns of their development and progress eventuating in noninvasive or various forms of invasive carcinoma.