Flow cytometric analysis of primary and metastatic bladder cancer

A total of 22 patients with high grade P2-4N+ transitional cell carcinoma of the bladder underwent flow cytometric analysis of nuclei obtained from paraffin embedded specimens from the primary (bladder) and metastatic (lymph node) sites. Tumor heterogeneity was defined as polyclonal aneuploidy of the primary tumor (not identified in the population studied) or as a difference in the deoxyribonucleic acid index of the primary and metastatic sites of 0.20 or more (8 patients). With these criteria 8 patients (36%) had heterogeneous tumors and 14 (64%) had homogeneous tumors. The median survival of 14 patients with aneuploid and 8 with diploid primary tumors was 17.5 and 8.0 months, respectively (p equals 0.08, Lee-Desu test). When patient survival was compared to the ploidy of the metastatic site, or in patients with diploid primary and metastatic lesions versus deoxyribonucleic acid aneuploidy at either the primary and/or metastatic site, the aneuploid tumors had a longer survival but this difference was not significant (p equals 0.13 and 0.23, respectively). Our study demonstrates the value of flow cytometry to identify primary metastatic tumor heterogeneity. It also suggests that the presence of metastasis may be a more important factor to define the biological potential of transitional cell carcinoma than is deoxyribonucleic acid ploidy.