Background: In an attempt to determine the biological significance of nuclear morphometric findings, measurements of mean nuclear volume (MNV) and nuclear roundness factor (NRF) were compared to the immunoreactivity of p53 expression and proliferating cell nuclear antigen (PCNA) in human bladder cancer.
Methods: MNV and NRF were measured using stereological methods. Expression of p53 and PCNA were determined by immunohistochemical staining. Specimens from 111 patients with previously untreated bladder cancer were analyzed.
Results: The mean MNV was 235.8 +/- 133.6 microm3 for the 81 patients with p53-labeling index (LI) less than 10% and 337.2 +/- 141.0 microm3 for the 30 patients with p53 LI greater than 10% (P = 0.008). There was no significant correlation between NRF and expression of p53. The mean MNV was 220.1 +/- 120.5 microm3 for the 67 patients with PCNA LI less than 28% (the mean value of PCNA LI) and 328.9 +/- 149.2 microm3 in 44 patients with PCNA LI greater than 28% (P = 0.0001). The mean NRF was 80.7 +/- 4.2 for the 67 patients with PCNA LI less than 28%, and 82.3 +/- 3.4 for the 44 patients with PCNA LI more than 28% (P = 0.04).
Conclusion: Nuclear morphometric findings may reflect the proliferative potential of cancer cells of the bladder, as indicated by findings of immunostaining for p53 and PCNA.