The prostate is a walnut-shaped gland that is part of the male reproductive system. It has two or more lobes, or sections, enclosed by an outer layer of tissue. The prostate is located in front of the rectum and just below the bladder, where urine is stored. It surrounds the urethra at the neck of the bladder and supplies fluid that goes into semen.
What are some common prostate problems?
The most common prostate problem in men younger than age 50 is inflammation, called prostatitis. Prostate enlargement, or benign prostatic hyperplasia (BPH), is another common problem. Because the prostate continues to grow as a man ages, BPH is the most common prostate problem for men older than age 50. Older men are at risk for prostate cancer as well, but it is much less common than BPH.
What are the symptoms of prostate problems?
The symptoms of prostate problems may include
- urinary retention—the inability to empty the bladder completely
- urinary frequency—urination eight or more times a day
- urinary urgency—the inability to delay urination
- urinary incontinence—the accidental loss of urine
- nocturia—frequent urination at night
- trouble beginning a urine stream
- weak or interrupted urine stream
- blockage of urine
- urine that has an unusual colour or odour
- pain after ejaculation or during urination
Different prostate problems may have similar symptoms. For example, one man with prostatitis and another with BPH may both experience urinary urgency. Sometimes symptoms for the same prostate problem differ among individuals. For example, one man with BPH may have trouble beginning a urine stream, while another may experience nocturia. A man in the early stages of prostate cancer may have no symptoms at all. Because of this confusing array of symptoms, a thorough medical exam and testing are vital.
What is the first test for detecting prostate problems?
Digital Rectal Exam (DRE)
To diagnose prostate problems, the health care provider will perform a digital rectal exam (DRE). A DRE is a physical exam of the prostate.
The first test for detecting prostate problems is a blood test to measure prostate-specific antigen (PSA), a protein made only by the prostate gland. Doctors recommend a PSA blood test be conducted starting at age 40 for men with a family history of prostate cancer. Some medical organizations like a family clinic or medical laboratories even recommend a PSA blood test be done to all men starting at age 40.
If urination problems are present or if a PSA blood test indicates a problem, additional tests may be ordered. These tests may require a patient to change his diet or fluid intake or to stop taking medications. If the tests involve inserting instruments into the urethra or rectum, antibiotics may be given before and after the test to prevent infection.
A PSA blood test is performed to detect or rule out prostate cancer. The amount of PSA in the blood is often higher in men who have prostate cancer. However, an elevated PSA level does not necessarily indicate prostate cancer. Much remains unknown about how to interpret a PSA blood test, its ability to discriminate between cancer and problems such as BPH and prostatitis, and the best course of action if the PSA level is high. When done in addition to a DRE, a PSA blood test enhances the detection of prostate cancer. However, the test is known to have relatively high false-positive rates. A PSA blood test also may identify a greater number of medically insignificant lumps or growths, called tumours, in the prostate.
What is a normal PSA level?
There is no specific normal or abnormal level of PSA in the blood, and levels may vary over time in the same man. In the past, most doctors considered PSA levels of 4.0 ng/mL and lower as normal. Therefore, if a man had a PSA level above 4.0 ng/mL, doctors would often recommend other examinations to determine whether prostate cancer was present.
However, more recent studies have shown that some men with PSA levels below 4.0 ng/mL have prostate cancer and that many men with higher levels do not have prostate cancer.
Various factors can cause a man’s PSA level to fluctuate. For example, a man’s PSA level often rises if he has prostatitis or a urinary tract infection. Prostate biopsies and prostate surgery also increase PSA level. Conversely, some drugs—including finasteride and dutasteride, which are used to treat BPH—lower a man’s PSA level.
The free prostate-specific antigen test, known as the free PSA test, is used to help detect signs of prostate cancer. The test measures the level of unbound prostate-specific antigen in the blood, which can help doctors to diagnose issues like inflammation of the prostate or cancer.
Free PSA tests are often used alongside PSA test to confirm a diagnosis or test results. Free PSA tests can also be used instead of a biopsy if the doctor suspects prostate cancer, but a biopsy may still be needed.
What is the difference between PSA and free PSA?
The tests are slightly different. A total PSA test measures all the PSA, including the antigens that are bound and those that are floating freely.
A free PSA test only measures the amount of PSA that is floating freely in the bloodstream, without being bound to a different protein.
Both tests are used to diagnose prostate issues. A person may have an increased risk of prostate cancer when they have higher levels of total PSA and lower levels of free PSA.
If the DRE or the PSA blood test indicates a problem may exist, the doctor may order additional tests, including
- urodynamic tests
- abdominal ultrasound
- trans-rectal ultrasound with prostate biopsy
- imaging studies such as magnetic resonance imaging (MRI)
- Computerized tomography (CT) scans.