Differential diagnosis and evaluation of the clinical course of transurethrally resected T1G3 urothelial carcinoma of the bladder by DNA image cytometry.

摘要

The value of DNA image cytometry in the differential diagnosis of 106 T1G3 urothelial carcinomas of the bladder and the long-term prognosis (recurrence-free interval, survival) of the patients was tested in comparison with Ta/T1G1 (n=30) and Ta/T1G2 carcinoma (n=54). Monolayer smears were prepared from three 50-microm-thick sections by a cell separation technique and were stained according to Feulgen. The DNA content of 250 epithelial cells, chosen at random, was determined using a TV-image analysis system CM-1 (Hund, Wetzlar, Germany). The DNA content of 30 lymphocytes served as an internal standard for the normal diploid value in every individual case. Different DNA cytometric parameters and the mean nuclear area were calculated. In comparison with G1- and G2-cases, the mean values of all DNA cytometric variables were markedly increased in the group of T1G3 cases, most obviously for the 5cEE, the mean ploidy and the ploidy imbalance (0.0006 > or = p > or = 0.0001). However, a remarkable overlay of the data distribution had to be considered. An aneuploid DNA stemline ploidy was highly characteristic for T1G3 urothelial carcinoma (sensitivity: 92%), but not sufficiently specific (57%). However, if increased values for the mean ploidy, the 2cDI, the 5cEE or the 9cEE (specificity: 86%-89%) were present additionally, the diagnosis of a T1G3 urothelial carcinoma could be made cytometrically. Follow-up data for survival (recurrence) analysis was available for 90 (82) patients of the T1G3 group. Using the median value as threshold, significant differences in survival were found for the mean ploidy only (p=0.0353). The length of the recurrence-free interval was significantly different for the entropy (p=0.0205), the 2cDI (p=0.0309) and the mean ploidy (p=0.0442). In conclusion, DNA single cell cytometry represents a highly relevant tool in the objective identification of T1G3 urothelial carcinoma of the bladder, with a sufficient sensitivity and specificity. Further, this method enables prediction of tumor recurrence if suitable variables are chosen. The long-term survival of patients with T1G3 urothelial carcinoma can be estimated by DNA cytometry only in a limited manner, possibly due to the fact that the causes of death in the mostly elderly patients will be independent from the limited tumor disease.