6th ESACP Congress, Heidelberg, April 7-11, 1999

A062
QUANTITATIVE ASSESSMENT OF BLADDER CANCER BY ACID LABILE DNA ASSAY
Gschwendtner A, Mairinger Th

Dept. Pathology, University of Innsbruck, Innsbruck, Austria

BACKGROUND: Effective noninvasive methods for monitoring bladder cancer patients and screening for bladder cancer, showing better performance than the methods currently in use would be desirable in order to detect urothelial cancers at an early, easily treatable stage. A rapidly hydrolyzed component of nuclear DNA has been described whose increase is linked to malignancy. Quantitative determination of acid labile DNA has been successfully applied to detect other neoplasms. This study investigates the potential of this method in detecting Transitional Cell Carcinomas. METHODS: Touch imprints of transurethral resection material of 62 cases with non-malignant urothelium (control group including reactive changes) and 94 cases of bladder cancer were analyzed. The full Feulgen hydrolysis profiles of the non-malignant and malignant urothelial cells were compared by measuring the staining density of the nuclei using digital image analysis after various hydrolysis times. 20 cells were sampled randomly out of the cells measured for calculation of the mean optical density (MOD). The MOD of each time was used to build the hydrolysis profile of a case. RESULTS: A hydrolysis time of 10 minutes turned out to be most discriminative between control and cancer cases. Applying a single threshold of MOD 101 resulted in a test sensitivity of 95,7%, a specificity of 94,4%, a positive predictive value of 98,3%, a negative predictive value and an area under the ROC curve of 0,97. CONCLUSIONS: The results of this pilot study suggest that measurement of the rapidly hydrolyzed component of DNA present in the nuclei of bladder urothelium offers a highly sensitive and reliable supplement to the qualitative and subjective procedures in existing cytology.