The more you know about the normal development and function of the prostate, where it’s located, and what it’s attached to, the better you can understand how prostate cancer develops and impacts a man’s life over time—due either to cancer growth or as a result of treatments.

Normal Anatomy

The prostate is a small, squishy Gland about the size of a walnut. It sits under the bladder and in front of the Rectum.
The bladder holds your urine until you are ready to void, and is like a balloon that gets larger as it fills with urine.
The urethra is a the narrow tube that connects to the bladder, runs right through the middle of the prostate, and runs through the length of the penis and carries both urine and semen out of the body. It is the hose that drains the bladder.
The rectum is the lower end of your intestines and it sits right behind the prostate.
The seminal vesicles are rabbit eared structures that store and secrete a large portion of your ejaculate. These structures sit on top of the prostate.
The neurovascular bundle is just that, a bundle of nerves and vessels that run along each side of the prostate. These nerves and vessels help control erectile function. They sometimes are a short distance away from the prostate, but sometimes they are adherent to the prostate itself.

Normal Physiology

The prostate is not essential for life, but is important for reproduction. It supplies substances that facilitate fertilization and sperm transit and survival. Enzymes like PSA (the same protein that is measured in the blood test that you may have already had) are actually used to loosen up semen to help sperm reach the egg during intercourse. (Sperm is not made in the prostate, but rather the testes.)

Other substances made by the seminal vesicles and prostate—such as zinc, citrate, and fructose—give sperm energy to make this journey. Substances like antibodies may protect the urinary tract and sperm from bacteria and other pathogens.

The prostate typically grows during adolescence under the control of the male Hormone Testosterone and its byproduct DHT, or dihydrotestosterone. Testosterone is primarily made in the testes, but a smaller amount is also made in the adrenal glands above your kidneys.

Prostate Zones

The prostate is divided into several anatomic regions, or zones. Most prostate cancer develops from the peripheral zone (the back of the prostate) near the rectum. That’s why a digital rectal exam (DRE) is a useful Screening test as the Doctor’s finger can feel the peripheral zone.

Ultrasound of the prostate

Ultrasound of the prostate

Lower urinary tract symptoms due to Benign Prostatic Hyperplasia (BPH), which is a non-cancerous prostate condition, typically develops from the transition zone that surrounds the urethra, or urinary tube (it is more in the middle of the prostate). This is why BPH may cause more difficulty with urination than prostate cancer typically does.

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