ENHANCED CYTOLOGIC DETECTION OF EARLY-STAGE MOUSE BLADDER-TUMOR FOLLOWING INDUCTION OF UROEPITHELIAL CELL SHEDDING

Previous studies from our laboratory have shown that some Escherichia coli endotoxins are capable of inducing massive normal urothelial cell shedding. In the present study we investigated whether endotoxin-indu ced shedding improves cytologic detection of early stage mouse bladder cancer. Mouse Madder tumor (MBT-2) cells were implanted intravesicall y in the submucosa of C3H female mice. Ten to 21 days later the bladde rs were irrigated with saline followed by instillation of endotoxin. T he bladder contents of each mouse were aspirated and examined cytologi cally together with the bladder wash specimen. Shedding of epithelial cells was observed in only 32% of the saline irrigated specimens compa red with 93% after endotoxin instillation (p < 0.00001). Analysis show ed an overall accuracy rate of 39% after saline barbotage versus 78% f ollowing endotoxin administration (p < 0.00001). These results indicat e that intravesical instillation of specific bacterial endotoxin signi ficantly increases the extent of cytologic detection of early stage su perficial bladder cancer.