ABSTRACT
The lobar concept of the anatomy of the prostate originally suggested by Lowsley1 is no longer particularly helpful. The accepted view today is that of McNeal2, who suggested that the prostate consists of three distinct zones: a central zone, transitional zone, and peripheral zone (Figure 1). The transitional zone is the site of development of benign prostatic hyperplasia, whereas the peripheral zone is where both prostatitis and prostate cancer mainly occur3. The explanation for these contrasting zonal susceptibilities to different diseases probably lies in their different phylogenetic origins. In primates, the gland is divided into a cranial prostate and a caudal prostate. In primates, the prostate is divided into a caudal prostate and a cranial prostate. In phylogenic terms, the cranial prostate is thought to be the precursor of the central zone whereas the caudal prostate is considered the precursor of the peripheral zone. Their fusion in humans creates a single gland that completely encircles the urethra, but the different zonal pathological tendencies underline their disparate origins.
