IMAGE CYTOMETRY DETERMINATION OF PLOIDY LEVEL, PROLIFERATIVE ACTIVITY, AND NUCLEAR SIZE IN A SERIES OF 314 TRANSITIONAL BLADDER CELL CARCINOMAS

Image cytometry was carried out on 281 superficial (Ta and Tl) and 33 invasive (T2 to T4) bladder cancers. The parameters used to characteri ze these bladder tumors were: (1) histopathological grading, (2) clini cal staging (3) tumor size, (4) deoxyribonucleic acid (DNA) index (DI) , (5) DNA histogram type (DHT), (6) percentage of euploid (diploid plu s tetraploid) cells, (7) percentage of polyploid cells (>5C DNA conten t), (8) proliferative activity (S phase fraction value), and (9) nucle ar area (NA). The proliferative activity of the tumors was not related to either histopathological grade or to clinical stage, but it was re lated to the DHT parameter, which made it possible to identify diploid , hyperdiploid, triploid, hypertriploid, tetraploid, and polymorphic t umors. The hypertriploid tumors exhibited a significantly lower prolif erative activity than the nonhypertriploid ones. Although both the DI and the NA values correlated significantly with histopathological grad ing, only the NA values correlated significantly with clinical staging We further observed that some grade III bladder tumors were definitel y diploid, whereas some grade I tumors were highly aneuploid. We thus hypothesize that the ploidy level of a given tumor reflects its age di rectly and its aggressiveness only very indirectly. In our opinion ane uploidy is only an indirect marker of agressiveness because it reflect s the fact that a malignant tumor is old, ie, has been present in a pa tient over a long period of time and has had ample time to express its malignancy at the clinical level. A significant relationship was acco rdingly obtained between tumor size and ploidy level with the highest proportion of aneuploid tumors and the highest percentage of polyploid cell nuclei being observed among the largest bladder tumors. HUM PATH OL 26:3-11. Copyright (C) 1995 by W.B. Saunders Company