Prostate cancer is cancer that starts in the prostate gland. The prostate is a small, walnut-sized structure that makes up part of a man's reproductive system. It wraps around the urethra, the tube that carries urine out of the body.
Cancer - prostate; Biopsy - prostate; Prostate biopsy; Gleason score
Causes, incidence, and risk factors
Prostate cancer is the most common cause of death from cancer in men over age 75. Prostate cancer is rarely found in men younger than 40.
People who are at higher risk include:
- African American men, who are also likely to develop cancer at every age
- Men who are older than 60
- Men who have a father or brother with prostate cancer
Other people at risk include:
- Men who have been around Agent Orange
- Men who use too much alcohol
- Men who eat a diet high in fat, especially animal fat
- Tire plant workers
- Men who have been around cadmium
Prostate cancer is less common in people who do not eat meat (vegetarians).
A common problem in almost all men as they grow older is an enlarged prostate. This is called benign prostatic hyperplasia, or BPH. It does not raise your risk of prostate cancer. However, it can increase your PSA blood test results.
The PSA blood test is often done to screen men for prostate cancer. Because of PSA testing, most prostate cancers are now found before they cause any symptoms.
The symptoms listed below can occur with prostate cancer, usually at a late stage. These symptoms can also be caused by other prostate problems:
- Delayed or slowed start of urinary stream
- Dribbling or leakage of urine, most often after urinating
- Slow urinary stream
- Straining when urinating, or not being able to empty out all of the urine
- Blood in the urine or semen
- Bone pain or tenderness, most often in the lower back and pelvic bones (only when the cancer has spread)
Signs and tests
A biopsy is needed to tell if you have prostate cancer. A sample of tissue is removed from the prostate and sent to a lab.
Your doctor may recommend a prostate biopsy if:
- You have high PSA level
- A rectal exam shows a large prostate or a hard, uneven surface
The results are reported using what is called a Gleason grade and a Gleason score.
The Gleason grade tells you how fast the cancer might spread. It grades tumors on a scale of 1 - 5. You may have different grades of cancer in one biopsy sample. The two main grades are added together. This gives you the Gleason score. The higher your Gleason score, the more likely the cancer is to have spread past the prostate:
- Scores 2 - 5: Low-grade prostate cancer
- Scores 6 - 7: Intermediate- (or in the middle) grade cancer. Most prostate cancers fall into this group.
- Scores 8 - 10: High-grade cancer
The following tests may be done to determine whether the cancer has spread:
The PSA blood test will also be used to monitor your cancer after treatment. Often, PSA levels will begin to rise before there are any symptoms. An abnormal digital rectal exam may be the only sign of prostate cancer (even if the PSA is normal).
Treatment depends on many things, including your Gleason score and your overall health. Your doctor will discuss your treatment options.
For early-stage prostate cancer, this may include:
If you are older, your doctor may recommend simply monitoring the cancer with PSA tests and biopsies.
If the prostate cancer has spread, treatment may include:
- Hormone therapy (medicines to reduce testosterone levels)
Surgery, radiation therapy, and hormone therapy can affect your sexual desire or performance. Problems with urine control are common after surgery and radiation therapy. Discuss your concerns with your health care provider.
After treatment for prostate cancer, you will be closely watched to make sure the cancer does not spread. This involves routine doctor check-ups, including PSA blood tests (usually every 3 months to 1 year).
You can ease the stress of illness by joining a support group whose members share common experiences and problems. See: Support group - prostate cancer
How well you do depends on whether the cancer has spread outside the prostate gland and how abnormal the cancer cells are (the Gleason score) when you are diagnosed.
Many patients can be cured if their prostate cancer has not spread. Some patients whose cancer has not spread very much outside the prostate gland can also be cured.
Hormone treatment can improve survival, even in patients who cannot be cured.
The complications of prostate cancer are mostly due to different treatments.
Calling your health care provider
Discuss the advantages and disadvantages to PSA screening with your health care provider.
You may lower your risk of prostate cancer by eating a diet that is:
- High in omega-3 fatty acids
- Similar to the traditional Japanese diet
Finasteride (Proscar, generic) and dutasteride (Avodart) are drugs used to treat prostate enlargement (benign prostatic hyperplasia, or BPH). If you do not have prostate cancer and your PSA score is 3.0 or lower, ask your health care provider about the pros and cons of taking these drugs to prevent prostate cancer.
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