Objective: To describe the histological characteristics of the ejaculatory duct and their importance in prostate adenocarcinoma.
Study design: Anatomical dissection of the prostate and seminal vesicles was performed in 20 autopsies of males without clinical evidence of prostatic pathology. Specimens were totally sampled to study the complete route of the ejaculatory ducts within the prostate, focusing specifically on the histological characteristics of the stroma enfolding the ducts.
Results: Ejaculatory ducts are covered by a distinct fibrous capsule that includes lymphatics and blood vessels with a specific spatial and architectural arrangement. Although easy to recognize in normal conditions, the positive nuclear immunostaining of epithelial cells with PAX-2 and PAX-8 may be of help to recognize the ejaculatory epithelium in problematic cases. These arteriolymphatic units made of hyalinized arteries and ectatic lymphatic vessels run parallel to the ejaculatory duct along its intraprostatic course and continue outside the prostate gland in the subadventitial tissue of seminal vesicles.
Conclusion: The ejaculatory ducts have a unique characteristic histology that allows its recognition in transrectal core biopsies. The issue matters in daily practice and may have prognostic implications in prostate adenocarcinoma since the invasion of this structure has been associated with a high percentage of extraprostatic disease.