Introduction
Urologists and pathologists have focused more and more on the anatomic structures of the human prostate gland and their relationship to prostate carcinoma development and prognosis since the resurgence of radical prostatectomy in the late 1980s. The accessibility of whole-mount slide preparation in the study of the prostate has greatly simplified this analysis.
This chapter concentrates on the anatomy of the prostate gland and analyzes how anatomic structures relate to the origin, development, and evolution of prostate carcinoma. The concept of zonal anatomy and its role in prostate carcinoma will also be described.
Anatomy and histology of the normal prostate gland
Embryology and development of the prostate gland
During the third month of gestation, the prostate gland develops from epithelial invaginations from the posterior urogenital sinus under the influence of the underlying mesenchyme [1]. The normal formation of the prostate gland requires the presence of 5α-dihydrotestosterone, which is synthesized from fetal testosterone by the action of 5α-reductase [2]. This enzyme is localized in the urogenital sinus and external genitalia of humans [3]. Consequently, deficiencies of 5α-reductase will cause a rudimentary or undetectable prostate in addition to severe abnormalities of the external genitalia, although the epididymides, vasa deferentia, and seminal vesicles remain normal [4].
During the prepubertal period, the constitution of the human prostate remains more or less identical but begins to undergo morphologic changes into the adult phenotype with the beginning of puberty.