IS ONE SINGLE PROSTATE BIOPSY HELPFUL FOR CHOOSING A MEDICAL-TREATMENT OF BENIGN PROSTATIC HYPERPLASIA - A QUANTITATIVE COMPUTERIZED MORPHOMETRIC STUDY

Objectives. Individual differences in proportion of stroma, epithelium , and luminal space components in benign prostatic hyperplasia (BPH) m ay explain the differences in clinical outcome of the patients treated with alpha-reductase inhibitors or alpha-blocking agents and other al ternative treatments. Knowledge of the individual proportions of these elements may orient the clinician toward different therapeutic approa ches. To determine whether a single prostate biopsy is representative of the whole adenoma, using quantitative morphometry, we have compared the percentage of smooth muscle cells and glandular cells in one pros tate needle biopsy and in the corresponding prostate adenoma removed b y open surgery. Methods. Quantification was made using a computerized image analysis system and immunohistochemical staining (actin antiacti n for the smooth muscle cells and anti-prostate-specific antigen (PSA) for the epithelial cells) in 14 patients who underwent retropubic pro statectomy. Results. Mean percentage of smooth muscle fibers, glandula r epithelium, and glandular lumina in the prostate biopsy were, respec tively, 34% (range, 20% to 42%, SD 5.9), 29% (range, 13% to 42%, SD 7. 2), and 20% (range, 13% to 30%, SD 4.8). In the corresponding prostate adenoma, they were, respectively, 38% (range, 28% to 45%, SD 4.7), 32 % (range, 25% to 40%, SD 4.5), and 19% (range, 13% to 34%, SD 6.1). Th e mean percentages of epithelial or glandular cells in the prostate bi opsy and the corresponding adenoma were not statistically different (P > 0.05), whereas those for the smooth muscle cell percentage were dif ferent (P = 0.02). However, a statistically significant correlation be tween the whole adenoma and the needle biospy sample was found in the percentage of smooth muscle cells (P = 0.028). Analyzing the morphomet ric data in conjunction with the serum PSA level and the volume of the adenoma, we found a statistically significant positive correlation be tween the volume of the adenoma and the ratio (percentage of epithelia l cells/serum PSA level) (P = 0.009, r = 0.67). Conclusions. Major dif ferences are found in the primary tissue composition of different hype rplastic prostates. Computerized histologic quantification of the diff erent components of BPH in the entire adenoma and a needle biopsy demo nstrate that a single prostate biopsy is representative of the entire prostate adenoma. Morphemetric data from a single biopsy of the prosta te adenoma in combination with the serum PSA level and the volume of t he prostate adenoma could therefore help to orient medical treatment o f BPH by patient selection based on the knowledge of the distribution of the various components of BPH.