Analysis of the mechanism of discrepant nuclear morphometric results comparing preoperative biopsy and prostatectomy specimens

Objectives. To explore the mechanism for the differing nuclear morphometric results between needle biopsy and surgical specimens of the prostate. Methods. In experiment 1, a comparison of mean nuclear area (MNA), volume-w eighted mean nuclear volume (MNV), and form factor (FF) for prostatic epith elial cells was performed between preoperative needle biopsy and prostatect omy specimens from 5 patients with benign prostatic hyperplasia (BPH), In e xperiment 2, a scheduled, sequential ex vivo needle sampling from the enucl eated prostates (at 0, 2, 6, and 24 hours after surgical resection) was als o performed for 7 patients with BPH. The prostatectomy specimens were left unfixed for 2 hours until the second needle sampling was done. Nuclear morp hometric parameters were measured on the needle-sampled as well as on the p rostatectomy specimens. Results, MNA, MNV, and FF of BPH cells measured on preoperative biopsy spec imens were smaller than those of surgical specimens in all 5 of the cases. The results of nuclear morphometry on the materials obtained by ex vivo nee dle sampling of prostates before and during fixation revealed that the MNA, MNV, and FF for BPH cells of 0-hour specimens were significantly smaller t han those for needle samples at 2, 6, and 24 hours after surgical resection as well as those for prostatectomy specimens. Conclusions. The present study provided further evidence that the ischemic damage caused by delayed fixation could result in a substantial change of t he nuclear morphology of prostate cells. An immediate start, as well as a r apid completion, of the fixation procedure seems critical for an accurate n uclear morphometry of prostatectomy specimens. UROLOGY 56: 342-345, 2000. ( C) 2000, Elsevier Science Inc.