Flow cytometric investigations of human bladder carcinoma compared to histological classification.

The DNA distribution has been investigated in biopsies from human bladder carcinomas by means of flow cytometry (FCM). The FCM analysis was based on a preparation method yielding a suspension of single cell nuclei. Biopsies from 45 patients were analysed. The results demonstrate a correlation between the degree of cellular anaplasia and the occurrence of cell populations with increased DNA content in the tumours. Cells with diploid DNA content constituted more than 90% of well-differentiated tumours and normal bladder mucosa. Cell populations with aneuploid DNA content occurred in almost all biopsies with cellular anaplasia estimated as grades II and III by microscopic examination. The results indicate that FCM analysis may be a valuable adjunct to histology. The possible prognostic significance of altered DNA distribution in bladder tumours is discussed.