Nuclear chromatin texture in prostatic lesions I. PIN and adenocarcinoma

OBJECTIVE: To document changes in the chromatin pattern in secretory cell nuclei from prostates with prostatic intraepithelial neoplasia (PIN) or adenocarcinoma. STUDY DESIGN: High-resolution images of nuclei were recorded, and a set of features descriptive of the chromatin texture and spatial distribution was computed. From this data set, features undergoing a monotonic trend of progression were selected and plotted to reveal trends in lesion progression. RESULTS: The nuclear chromatin in secretory cells in prostates with either PIN or malignant adenocarcinoma undergoes distinct and statistically significant changes in its texture and spatial distribution. Two trends of progressive change were observed. First, the values of a number of features descriptive of the clumpiness of the chromatin increase from values found in normal prostates to those recorded for nuclei from low grade to high grade PIN lesions. The second trend is a decrease in the values of the same features from those found in nuclei from high grade PIN still facing an intact basal cell layer to those no longer facing such a layer. This may be the first detectable step in progression towards development of a malignant lesion. There is a further decrease in nuclei in glands immediately adjacent to adenocarcinoma and in malignant lesions themselves. CONCLUSION: The described changes may lend themselves to the monitoring of lesion progression or of response to treatment or to chemopreventive intervention.