Objective: To quantitatively evaluate the changes in the secretory cells in nodular hyperplasia of the prostate after treatment with finasteride.
Study design: Secretory cell nuclear and nucleolar measurements were performed with an image analyzer in hematoxylin-and-eosin-stained sections of 20 untreated and 20 finasteride-treated cases of nodular hyperplasia. An immunoperoxidase method was used to stain the secretory cells with a monoclonal antibody-directed, anti-prostate specific antigen (PSA). The size of prostates was determined by transrectal ultrasound. For both groups the serum PSA values were determined.
Results: After six months of treatment with finasteride, the prostates shrank by approximately 20% with the therapeutic regimen (as determined by transrectal ultrasound), whereas the serum PSA values decreased by 30% (before therapy, < 4.00 ng/mL). The secretory cells appeared smaller than those from the untreated group of patients, and the cytoplasm staining of the PSA marker was slightly diminished. Karyometric analyses showed that the nuclear and nucleolar size were smaller in comparison with the controls. In particular, the mean nuclear and nucleolar area in the treated group were, respectively, 34.12 and 1.424 micron 2, whereas in the untreated group the values were 40.46 and 2.261.
Conclusion: Reduced androgen stimulation after treatment with finasteride induces involution of secretory cells. This may be responsible for the decrease in the serum PSA level and may contribute to the reduction in prostate size.