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Weighs approximately 20 gm in the normal adult male.
A retroperitoneal organ encircling the neck of the bladder and urethra and is without of a distinct capsule.
Divided into four biologic and anatomical zones: peripheral, central, transitional and anterior febricula stroma.
The peripheral zone is the largest of the zones, encompassing approximately 75% of the total prostate glandular tissue in men without BPH.
Most prostate cancers originate in the peripheral zone.
The peripheral zone lies posterior and laterally.
The central zone is smaller and extends primarily around the ejaculatory ducts.
The transition zone is usually the smallest of the 3, occupying only 5% of the prostate volume in men younger than 30 years.
A tubuloalveolar organ with glandular spaces lined by epithelium.
Glands lined by two layers-a basal layer of cubical epithelium covered by a layer of columnar secretory cells.
Papillary inbuddings of the epithelium may occur.
Prostatic calculi formed from calcification and precipitation of prostatic secretions, occurring between the transition zone and the compressed peripheral zone.
Prostatic calculi are usually composed of calcium phosphate and are not considered clinically significant.
Hidden within the pelvis, bordered anteriorly and laterally by bones and by the bladder above making examination and imaging problematic.
Androgens control its growth.
The majority of mature prostate cells are dependent on androgens for survival, and if withdrawn apoptosis will result.
The similarities in BPH among identical twins suggest a hereditary influence.
BPH tends to progress, as cross-sectional studies suggest that the growth rate of the prostate decreases with age.
In patients aged 31-50 years, the prostate doubling time averages 4.5 years.
In men aged 51-70 years, the prostatic doubling time is approximately 10 years, while in men older than 70 years, the doubling time increases to more than 100 years.
A 5-year longitudinal study of 631 community men aged 40-79 years from Olmsted County, Minnesota demonstrated an average annual prostate growth rate of 1.6%, and in this study it remained essentially constant regardless of age, although men with larger prostates tended to have higher growth rates.
The average prostate weighs approximately 20 g by the third decade and remains relatively constant in size and weight unless BPH develops.
The typical patient with BPH has a prostate that averages 33 g.
Only 4% of the male population ever develops prostates of 100 g or larger.
The blood supply of the prostate comes primarily from branches of the inferior vesical artery, which is a branch of the internal iliac artery.
When the inferior vesical artery reaches the prostate just at the vesicoprostatic border, it branches into 2 groups of arteries: One penetrating group passes directly into the prostate toward the interior of the bladder neck.
Upon reaching the prostatic interior near the urethra, most of these branches turn distally and parallel the prostatic urethra, while others supply the median lobe.
Primitive prostate stem cells and progenitor cells survive androgen depletion and are responsible for driving organ regeneration when subsequently stimulated by androgens.
Most hyperplasias occur in the transitional zone.
Prostate size alone is not a reliable or accurate predictor of the presence or degree of urinary outlet obstruction.
Most carcinomas originate in the peripheral zone.
Main function is to produce most of the fluid in semen.
Size and shape similar to that of a walnut.
The estimate of prostate size is generally underestimated on digital exam.
In young males it is the size of a pea, and undergoes a growth spurt during puberty under the influence of hormones.
Normal adult size by age 20 years and then begins growing as early as age 25 years.
In later life can be the size of a baseball.
Prostate specific antigen is the most important product of the gland and it liquefies other products in the semen, turning it into a thin milky discharge.
Prostate specific antigen is the most important product of the gland and it liquefies other products in the semen, turning it into a thin milky discharge.
Semen helps to deliver sperm and is crucial for successful conception.
Male orgasm results in muscles squeezing prostate fluid, including prostatic specific antigen, and other substances into the urethra, through tiny pores where it mixes with fluid from the seminal vesicles and sperm, forming semen.
Small cell neuroendocrine tumors of the prostate account for 1-2% of cases of prostate cancer.
Neuroendocrine cells are found throughout the prostate and can secrete corticotropin, serotonin, chromogranin A, neuron-specific enolase, bombesin, calcitonin, and parathyroid hormone related protein.