An enlarged prostate is a problem most men will confront in their lifetimes. If a man lives long enough, he’ll most likely have an enlarged prostate.
The prostate is a male reproductive gland tasked with producing the fluid that carries sperm out of the body during ejaculation. The prostate surrounds the urethra, the tube through which urine passes during urination. As men age, the prostate gland grows bigger. It is originally about the size of a walnut, often increasing in size by the age of 40 to the size of an apricot. By the time a man is 60 years old, his prostate gland may have enlarged to the size of a lemon. The enlarged prostate ends up squeezing the urethra like a clamp on a garden hose, causing the flow of urine to become weak and slow. The condition is also known as benign prostatic hyperplasia. It’s not cancerous, and it doesn’t increase a man’s risk of contracting prostate cancer. More than 50 % of men in their sixties have symptoms of enlarged prostates due to benign prostatic hyperplasia, and that number rises to many as 90 percent when men reach their seventies and eighties.
Why Enlarged Prostate Occurs
The causes of enlarged prostate are not well understood. The only two risk factors doctors have been able to associate with enlarged prostate are growing old and having a functioning set of testicles. Men who have had their testicles removed when they were young do not develop benign prostatic hyperplasia.
Other explanations for an enlarged prostate include:
- Decreased testosterone level. The amount of testosterone in the blood decreases as a man ages. When that occurs, the proportion of naturally occurring estrogen in a man’s body increases, and may promote growth of the prostate.
- Increased DHT level. The prostate derives a substance called dihydrotestosterone, or DHT, from testosterone. Even though blood testosterone levels drop in older men, DHT production doesn’t slow down, so high levels of DHT continue to build up in the prostate. This could lead to the growth of prostate cells.
- Genetics. It has also been suggested that genetic instructions inside some prostate cells may order them to activate later in life and begin to grow.
An enlarged prostate also can result from a prostate infection or from prostate cancer, although those occur less frequently and are not as inevitable as BPH.
The symptoms of enlarged prostate always revolve around a problem with the ability to urinate. Men might find that they can only maintain a hesitant, weak stream that frequently stops. They also may need to urinate more frequently, because the bladder is not completely emptied with each episode of urination, particularly at night. There is usually no pain involved in BPH; if there is pain, it could mean an infection has occurred.
There’s no way to prevent benign prostatic hyperplasia. It occurs as a function of aging.
Enlarged Prostate: Diagnosis and Treatment
The means used by physicians to diagnose an enlarged prostate include:
- Rectal exam. The prostate gland can best be felt through the rectal cavity. A doctor inserts a gloved, lubricated finger into your rectum to feel how large the prostate gland is, and whether there are any abnormalities, such as an area that is hard or lumpy.
- Urine and blood tests. Results of a urine test can suggest that the prostate may be enlarged due to infection, while a blood test can measure prostate specific antigen (PSA), which is high when prostate cancer is present. The United States Preventive Services Task Force recently recommended against PSA tests for prostate cancer, but many medical experts say men should still get screened. PSA tests may also be used to calculate PSA density, which is your PSA score divided by the size of your prostate (determined through ultrasound). A high PSA density is more likely to be indicative of cancer; a low PSA density suggests prostate enlargement.
- Ultrasound exam. Sound waves are directed at the prostate through a probe inserted in the rectum. The echoes of these sounds waves then create an image of the prostate on a television screen.
- Urine flow exam. You urinate into a special device that gauges the speed and strength of urine flow.
- Cystoscopy. A small tube is inserted into the penis through the urethra, allowing a doctor to see the inside of the urethra and bladder, and to visualize areas compressed by an enlarged prostate.
Benign prostatic hyperplasia-related enlarged prostate is most often treated through drug therapy or surgery:
- Drug therapy. Medications known as alpha-blockers relieve pressure and restore urine flow by relaxing the muscles near the prostate. They don’t reduce the size of the prostate, however. Another drug known as Proscar (finasteride) is able to reduce the size of the prostate gland by blocking an enzyme that normally interacts with testosterone to stimulate prostate growth. By stopping this interaction, finasteride slows the growth of the prostate gland and even reduces the size of the prostate, which could reduce blockage.
- Surgery. There are several surgical options for treating BPH-related enlarged prostate. In extreme cases, the prostate may be removed. A more common surgical approach — accounting for 90 percent of benign prostatic hyperplasia surgeries — is to widen the urethra by trimming excess tissue away from the gland. This option generally doesn’t cause some of the complications of other prostate surgeries, such as incontinence and impotence.
Unfortunately, an enlarged prostate can reoccur after surgery that trims excess prostate tissue, or if a man stops taking his medication. Untreated enlarged prostate can lead to urinary tract infections, kidney or bladder stones, or urinary retention and kidney damage. That’s why it’s so important to see a doctor if you have symptoms that may suggest a prostate problem.