Prostate Gland and It’s Conditions – Applied Anatomy and Physiology

In Greek the word “prostates” means “to stand before”. Anatomist Heropilus named it as such because the prostate stood before the testes, as he saw it. Now we know that it is a part of the male reproductive system.

The prostate is a small gland made up of about fifty smaller glands. At birth it is about the size of a pea and by the age of fifty years to the size of a walnut. It is surrounded by a fibrous capsule which does not allow it to grow to the exterior. Inward growth continues and constricts the urethra. Fortunately this is a slow process and manifests itself in later life. 50 % of men in their 60s are affected by this condition. However, 90% of men in their 70s and 80s are affected by benign hypertrophy of the prostate.

It is supplied by a branch of the internal iliac artery and venous return is by the iliac vein. The prostate gland contains many bundles of smooth muscles, about 50 small glands, each about the size of a pea in early childhood. In adulthood it becomes the size of a walnut. The prostate is a part of the male reproductive system and is located inferior to the bladder; it surrounds the initial part of the urethra and the ejaculatory duct.

The Location of the Prostate gland

The main function of the prostate gland is the production of a milky fluid which is said to energize the sperm and provide a medium for the sperm to swim, upon ejaculation. During ejaculation of semen, this milky fluid is discharged into the urethra. Sperm cells are equipped with the flagellum which allows them to swim, hopefully to the ova.

Frequency of Common Conditions of the Prostate gland.

One quarter of men over the age of 55 years are likely to have prostatic conditions.
Half of all men over the age of 70 are likely to have similar conditions.

It is recommended that every man aged 50 or more has his prostate examined each year.
For men with positive history annual check ups should begin at the age of 40 years.

Men who have their testes removed before puberty do not develop hypertrophy of the prostate. It is for this reason that BHP is said to be male sex hormone related.

Dihydrotestosterone (DHT) is testosterone derivative found in the prostate. Animals which lose the ability to produce DHT as they age do not develop BHP. However, these studies could not be replicated in human subjects. Older men continued to accumulate DHT in the prostate and it continued to develop BHP.

Prostatitis (Inflammation of the prostate) is the term used to describe inflammation of the prostate. It is sometimes caused by bacterial infections. In most cases prostatitis is due to idiopathic causes. Idiopathic prostatitis is difficult to manage because the pathophysiology is not clearly understood. However, when prostates is due to bacterial agents it can be managed easily because the antibiotics concentrate in the prostate gland.

Prevalence of Prostate cancer – Australia

Cancers of the prostate gland affect one out of eighteen Australian men. It is more common in the over 65 age group. The cause of prostate cancer is still unknown. However, around three thousand 3,000 men in Victoria are diagnosed each year to be suffering from ca of the prostate gland. Old age and a positive family history are definite contributing factors. The growth of Ca of the prostate is hormone related. Hence men with Ca of the prostate are often prescribed a female sex hormone called stilboestrol.

In the early stages of malignancy cancerous cells are located within the prostate gland. Hence early diagnosis is essential to cure and management. However, as the malignant cells proliferate the vascular and lymphatic systems, treatment and management become more difficult. Cure becomes impossible.

In the terminal stages death is usually due to metastasis which results in erosion of blood vessels, bones and muscles.

Pathophysiology of Prostate enlargement: Benign Prostatic Hyperplasia (BPH) is non-malignant hypertrophy of the prostate gland. It becomes more common as men get older. The urethral obstruction is a result of the squeezing action of the enlarged gland. Eventually the urethra fails to open when the bladder contracts for urination. The reasons for the enlargement are not clearly understood but a positive family history and
Signs and Symptoms of an Enlarged Prostrate:

• Inability to initiate stream.

• Going to the toilet at frequent intervals but voiding only small amounts each time.
• Acute retention of urine is seen. This may cause pain due to bladder distension.
• Hematuria may be present. The internal bleeding is due to excessive distension and damage of blood vessels.
• Inflammation of the urinary bladder is called cystitis. It is due to distension, irritation and low grade infections.
• Temporary relief is often obtained by inserting a foley catheter into the bladder. This should be done by a qualified practitioner using an aseptic technique.
• Chronic and ongoing retention is less common but may result in unsafe distension of the bladder which is often painless.
• Chronic retention can cause damage to the ureters, pelvis and kidney tissue.
• Damaged kidneys produce hypertension by increasing the production of angiotensin – a powerful vasoconstrictor.

Listed below are the three most common conditions of the prostate gland along with some treatment choices

Prostatitis: This is usually caused by bacteria and as such it is treated with antibiotics. The type of antibiotic used will depend upon bacterial sensitivity.

Benign Hypertrophy: This is often treated with smooth muscle relaxants or medications which shrink the size of the prostate. Surgery is indicated to widen the channel (TURP) and/or to reduce the size of the prostate (TUIP).

Malignant Conditions: These are diagnosed after obtaining the clinical history, doing the necessary examinations and investigations. Treatment will depend upon the stage of the cancer, the general health of the patient and the patient’s choices. In general, it is fair to say that management will include medical supervision, surgery, radiotherapy, hormonal therapy and cytotoxic therapy.

Useful Sources of Information: Surgeons, Medical doctor, Registered Nurses, Enrolled Nurses, Remote Health Care Workers, The Cancer Council Victoria: Support Service Tel. (03) 131 120 and Australian Kidney Foundation Tel. (03) 9866 3300.

Key Points:

The prostate gland is a part of the male reproductive system. It manufactures fluids which nourishes the ejaculated sperm at entry into the urethra.
Benign Hypertrophy of the prostate, inflammation due to infection and idiopathic causes and cancerous changes are the most common problems associated with the prostate gland.

Recommendation: Men over 50 years should be examined and tested for prostate annually.
Men with family history should consider annual examination from age 40 years.

Diagnosing Conditions of the Prostate: As stated earlier prostate conditions affect 90 % of men between the ages of 70 to 80 years have conditions of the prostate which need to be managed and/or treated. Appropriate diagnosis is most important for successful management of this condition. The following are some of the most frequently used diagnostic tools.

Accurate history should be taken by a Registered Nurse and/or qualified physician, surgeon.

Rectal examination to check the size of the prostate by palpation of the exterior boundary. This is usually done on the first so that an overtly malignant lesion is not missed. The urologist or general practitioner inserts a gloved finger into the rectum. He/She then palpates the prostate for a general idea of size and condition of the prostate.

Laboratory tests should include blood tests, body fluids and cell examinations (biopsies).

Ultrasound scans. These scans should be done when there is a suspicion of prostate malignancy. The urologist may order a highly specialized test with rectal ultrasound. Here, a probe is inserted into the rectum. It directs sound waves at the prostate. The echo pattern of the sound waves are picked up as an image. These images can be used to aid diagnosis.

Urinary flow studies including the assessment of residual urine should be done for proper diagnosis, management and treatment.

Cystoscopy. This procedure involves anaesthetising the patient and passing a cystoscope into the urethra to visually examine the urethra and bladder.

Intravenous Pyelography (IVP) involves the injection of a radio opaque dye into a vein (venous system). Then x-rays are taken as the dye is excreted by the kidneys. This dye makes the urine visible and helps to show up obstruction or blockages of the urinary tract.

Prostate-Specific Antigen (PSA) blood test. This test is specific for cancers of the prostate. However, it is a relatively new test and it’s ability to conclusively separate cancer from benign prostate conditions has not been clearly established. However, to rule out cancer the physician may order this test and interpret the results with clinical information.