Pathological changes in benign and malignant prostatic tissue following androgen deprivation therapy

Area of Science:

• Oncology
• Pathology
• Urology

Background:

• Neoadjuvant androgen ablation therapy is used for operable prostate cancer.
• This therapy induces involutional changes in the prostate.
• Residual cancer may be focal after treatment.

Purpose of the Study:

• To describe the morphological and biological changes in prostate cancer following neoadjuvant androgen ablation therapy.
• To evaluate the impact of these changes on pathological staging and grading.
• To assess the potential for tumor downstaging.

Main Methods:

• Review of retrospective studies and prospective trials.
• Morphological analysis of treated prostatic adenocarcinoma and benign prostatic tissue.
• Electron microscopy to investigate mechanisms of involution.
• Comparison of proliferation rates and aneuploidy in treated versus untreated tumors.

Main Results:

• Androgen deprivation therapy causes significant involutional changes, including loss of architecture, vacuolization, and nuclear pyknosis.
• Residual adenocarcinoma is common, though often focal.
• Treated tumors may show a high Gleason score paradoxically, but with reduced proliferation and aneuploidy.
• Benign prostatic tissue also exhibits treatment-related changes.
• Pathologic downstaging is suggested but local control impact is unclear.

Conclusions:

• Neoadjuvant androgen ablation therapy induces dramatic involutional changes in prostate cancer, requiring pathologist awareness.
• Conventional grading of pretreated adenocarcinoma can be misleading.
• While downstaging is suggested, its clinical significance regarding local control requires further investigation.