Prostate Cancer
Definition
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. 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.
Causes/Risk Factors
People who are at higher risk include:
- African-American men, who are 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 exposed to agent orange
- Men who eat a diet high in fat, especially animal fat
- Tire plant workers
- Painters
- Men who have been in contact with cadmium
Prostate cancer is less common in people who do not eat meat (vegetarians).
Warning Signs/Symptoms
In its early stage, bladder cancer can be asymptomatic or mimic symptoms of benign conditions, such as bladder stones, enlarged prostate or urinary tract infection. If symptoms do appear they should be evaluated as soon as possible. Warning signs include:
- Elevated PSA. 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.
- Abnormal digital rectal exam may be the only sign of prostate cancer (even if the PSA is normal).
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 the bladder
- Blood in the urine or semen
- Bone pain or tenderness, most often in the lower back/pelvic bones (only when the cancer has spread)
Diagnosis
This will normally include some or all of the following:
- A prostate biopsy is needed to tell if a patient has prostate cancer. A sample of tissue is removed from the prostate and sent to a lab.
A prostate biopsy is recommended when:-
- PSA level is elevated
- 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 is a measure of cancer aggressiveness as well as a measure of how fast the cancer might spread. It grades tumors on a scale of 1 - 5. There may be different grades of cancer in one biopsy sample. The two main grades are added together. This gives the Gleason score. The higher the Gleason score, the more likely the cancer is to have spread outside the prostate:
- Scores 2 - 6: Low-grade prostate cancer
- Scores 7: Intermediate- (or in the middle-) grade cancer.
- Scores 8 - 10: High-grade cancer
The following tests may be done to determine whether the cancer has spread:
- MRI prostate to image the prostate capsule and to assess if there is any invasion into the seminal vesicle glands that sit next to the prostate.
- CT scan of abdomen/pelvis to assess for spread to lymph nodes and other organs
- Bone scan to assess for spread of cancer to the bones
Treatment Options
Treatment depends on many factors, including Gleason score and the patient’s overall health. How well the patient does depends on whether the cancer has spread outside the prostate gland and how abnormal the cancer cells are (the Gleason score) at diagnosis. 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 and chemotherapy and newer agents prescribed by an oncologist can improve survival, even in patients who cannot be cured.
There are numerous treatment options: -
Early-stage prostate cancer
- Active surveillance - involves simply monitoring the cancer with
PSA tests and biopsies may be recommended, particularly for low risk disease or in older patients.
- Surgery (radical prostatectomy) which can be performed
robotically
laparascopically
open procedure
- therapy, including
external beam radiation therapy
brachytherapy
cyberknife
proton beam therapy
- Cryotherapy – freezing whole (total) or half (focal) of the prostate gland
- High-Intensity Focused Ultrasound (HIFU) applies high-intensity focused sonic energy to locally heat and destroy diseased or damaged prostate tissue through ablation. This is not yet FDA approved in the U.S.
For more advanced prostate cancer that has spread:
- Hormone therapy (medicines to reduce testosterone levels)
- Surgery to remove the testicles that make testosterone.
- Chemotherapy agents like docetaxol
- Immune therapy with Provenge ®
- Newer agents – Abiraterone (zytiga), cabazitaxel, enzalutamide,
Prevention
Diet that can lower risk of prostate cancer is:
- Low-fat
- Cutting down on red meat
- Vegetarian, similar to the traditional Japanese diet
- High in omega-3 fatty acids
- Enriched with vitamin D
Medication
Finasteride (Proscar, generic) and dutasteride (Avodart) are drugs used to treat prostate enlargement (benign prostatic hyperplasia, or BPH). There is some evidence that taking these drugs can help prevent prostate cancer.
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