[Clinical observation on in situ carcinoma of the bladder and related conditions]

Clinical course and histological findings of 692 patients with bladder tumor were reviewed to reveal the statistics and clinical profile of carcinoma in situ and its related conditions in the urinary bladder. Primary papillary intraepithelial lesions were found in 83 cases (12.0%), whereas flat intraepithelial carcinoma was found in 16 cases (2.0%), 10 as primary and 6 as secondary tumors. In 35 cases (3.5%), the bladder lesion was flat and rather difficult to find by cystoscopy, and initially considered as chronic cystitis or flat carcinoma in situ. Post-operative histological diagnosis, however, revealed micro- or apparent invasion beyond the basement membrane. Thus they were tentatively classified as clinical carcinoma in situ. The result of the radical surgical treatments for the clinical carcinoma in situ was very poor with a rough 5-year survival of 19%. The management of primary or secondary flat intraepithelial carcinoma was carried out by radical surgery or bladder sparing operation followed by intravesical instillation of cytotoxic agents. The results of these procedures remain uncertain. Some confusion in terminology of carcinoma in situ is discussed and the term "flat carcinoma" was recommended to indicate carcinoma in situ and its related conditions.