Application of confocal scanning laser microscopy to 3-D DNA image cytometry of prostatic lesions

To explore the potential of three-dimensional (3-D) image cytometry for the measurement of DNA content in prostatic specimens using confocal scanning laser microscopy (CSLM) and 3-D image analysis.

Thick tissue slices (100 microns), stained for DNA with chromomycin A3, from four patients with benign hyperplasia, prostatic intraepithelial neoplasia (PIN), well- and poorly differentiated adenocarcinoma of the prostate, were studied. Two different blocks from the same slice were studied for each case. Cell nuclei were segmented automatically. DNA content and nuclear volume were measured.

DNA histograms showed a single peak in the diploid range for the hyperplasia and PIN cases. For the case of well-differentiated carcinoma, two peaks were observed, one in the diploid range and one in the tetraploid range. The two peaks were observed on two different blocks of the same tissue slice. Poorly differentiated carcinoma was characterized by an aneuploid distribution. For the cases of PIN and carcinoma, we observed a considerable variation in nuclear volume.

The results indicate the potential of 3-D image cytometry for the measurement of DNA content in prostatic specimens while preserving tissue architecture.