Prostate Facts, Functions and Diseases
Prostate is known as the largest accessory gland of the male reproductive system. The gland resembles the shape of an inverted cone or a pyramid. In normal adult it weighs about 20 gm. It synthesizes an alkaline fluid that provides about 30% of the volume of seminal fluid. The nature of the prostatic secretion is watery, opalescent fluid which contains calcium, acid phophatase, citric acid, lipids and proteins.
Location and size of the prostate gland
Prostate is located between the base of the urinary bladder and the urogenital diaphragm. Prostate surrounds the first portion of the urethra and composed of lobules that drain directly into the urethra. It is approximately 3 cm long from apex to base and 3.5 cm across the base; it is roughly the size of a chestnut.
Function of the prostate gland
- One of the most important prostate functions is the secretion of alkaline fluid that adds to the bulk of the semen. Semen is a mixture of fluid from three accessory male sex glands i.e. seminal vesicles, bulbourethral and prostate; semen is discharged during ejaculation in men and contains sperms.
- Prostatic secretion imparts the unique characteristic odor to the semen.
- A slightly alkaline nature of the prostatic secretion is thought to play an important role for successful fertilization of the ovum.
- The alkaline nature of the prostatic fluid enhances the motility of sperm. Sperms become optimally motile when pH of the surrounding fluids reaches to about 6 to 6.5.
Disorders of the prostate gland
This is a type of inflammation caused by bacteria similar to those that inflict urinary tract infections. It can be acute, chronic or granulomatous. Usually the bacteria become implanted in the prostate due to reflux of urine into the prostate or sometimes the bacteria can spread through its lymphatic routes. Other causes of pancreatitis may include:
- Urethral dilation
- Cystoscopy (examination of bladder with cystoscope)
- Surgical manipulation of urethra or prostate
- Recurrent urinary tract infections
- Fungal infection in immunocompromised patients
Benign prostatic hyperplasia
Also called nodular hyperplasia; hyperplasia generally means increase in the number of normal cells which in this specific case results in prostatic enlargement. It is a common age related disorder and very common in men over 50 years of age. The 90% of the patients are in their 80s. Large nodules are also formed in the gland. Patients often complain of poor prolonged urinary flow, hesitancy and a sensation of incomplete emptying. There is variable degree of urinary retention due to obstruction of urethra. A painful distended bladder may develop when patients are suddenly unable to urinate. As the prostate facts suggest, the prostatic androgen hormones play an important role in the development of this disorder.
It is one of the typical prostate diseases of men after 50 years of age with an average age of diagnosis is 72 years old. It is the most common type of cancer in adult males and second most common cancer related death in men. Patients with a laboratory value of prostate specific antigen (PSA) more than 4 ng/ml will have prostate cancer on biopsy. Risk factors include:
- Advancing age is the most important risk factor
- First degree relatives (father and brothers)
- High saturated fat diet
- Cigarette smoking
- Black men (rare in Asians)
After 45 years of age some degree of prostatic abnormality is invariable; it is as much a sign of ageing as graying of the hair.