Histopathological aspects of transitional cell carcinoma of the bladder: Analysis of 20 years experience

Background: In this study we used histopathological examinations performed over a 20-year period to describe the characteristics of newly diagnosed transitional cell carcinoma (TCC) of the bladder in relation to patient age, and to verify changes in the TCC over different periods of observation or in relation to patient age. Methods: We reviewed all histopathological examinations performed from January 1979 to December 1998 in patients undergoing surgery who were newly diagnosed with TCC of the bladder. All examinations were performed by the same pathologist and reviewed by two pathologists. In each case analyzed, we evaluated T classification of the tumor, histological grade, size, localization, growth type, multiplicity and carcinoma in situ (CIS). Results: The study population included 3113 men and 620 women. The mean patient age was 66.31 +/- 10.84 years. A high percentage of Ta (52.2%) and T1 (27.7%) tumors were found. The number of cases observed and, in particular, the percentage of Ta tumors increased significantly and progressively from the first (1979-1983 = 376 cases; Ta = 37.8%) to the last (1994-1998 = 1732 cases; Ta = 56.3%) period of observation (P < 0.001). A significant difference in the distribution of histological grade and T classification in the different age decades was apparent (P < 0.001); in particular, for G1 and Ta tumors there was a trend to decrease, whereas for G3, T1 and T2 tumors there was a tendency to increase with age decades. Conclusion: In our analysis, age of patient and the period of examination significantly influenced different pathological characteristics of newly diagnosed TCC of the bladder.