Prospective registration of all patients in a geographical region with newly diagnosed bladder carcinomas during a two-year period.

OBJECTIVE: To report the age, stage and grade of all patients with newly diagnosed bladder carcinoma in a well-defined geographical region and to compare this cohort with previous reports which come mainly from large referral centres.
MATERIAL AND METHODS: All newly diagnosed bladder carcinoma patients (n = 701) in Western Sweden were prospectively registered during a 2-year period (1987-88). The histopathological material was re-examined by a reference pathologist. All the original clinical records were reviewed by one urologist 5-7 years after diagnosis. Demographic data, tumor grade, stage, multiplicity, presence of carcinoma in situ and lymphatic invasion are presented.
RESULTS: The mean age at diagnosis was 70.5 years. Grade and stage increase with age. The proportion of non-invasive tumors (55%) is higher than in any previous Scandinavian report. The age-standardized incidence in bladder carcinoma among men in the largest city (Göteborg) is 55% higher than in the rest of the region (p<0.0001). Deviations between the primary pathologist and the reviewer with regard to tumor grade were particularly seen in tumors of grades I and II.
CONCLUSIONS: Differences in mean age, stage and grade distribution were found between the present report, which included all patients with newly diagnosed bladder carcinoma in a geographical area, and other reports, which mainly comprised patients from large treatment centres. These differences can probably and mainly be explained by selection factors such as various degrees of inclusion of low-grade papillary tumors.