Prostate cancer
Introduction:
Prostate
cancer is a cancerous tumor in the prostate gland, a small walnut-sized
gland in men that makes seminal fluid, which helps carry sperm out of
the body. The prostate is located beneath the bladder and surrounds the
urethra, the tube that carries urine out through the penis. Prostate
tumors can be benign or cancerous. With benign tumors, the prostate
enlarges and squeezes the urethra, interrupting the normal flow of
urine. This condition, benign prostate hyperplasia, is common and rarely
life threatening. Prostate cancer -- one of the most common kinds of
cancer in men -- can spread beyond the prostate gland and be life
threatening.
Prostate
cancer is the third most common cause of cancer deaths in men of all
ages and is the most common cause of death from cancer in men over 75
years old. Men younger than 40 rarely have prostate cancer. Men at
higher risk include African-American men older than 60, farmers, tire
plant workers, painters, and men exposed to cadmium. The lowest number
of cases occurs in Japanese men and vegetarians.
However,
most cancerous tumors in the prostate tend to grow slowly and either do
not spread or cause harm for decades. When caught early, prostate
cancer can be treated successfully in more than 90% of cases. Men 50
years old and older should talk to their doctors about being screened
for prostate cancer.
Signs and Symptoms:
Many people with prostate cancer have no symptoms at all, especially in the early stages.
Some symptoms that may indicate prostate cancer include:
- Difficult and painful urination
- Frequent urination, especially at night, and a feeling that you need to urinate even when your bladder is empty
- Incomplete emptying of the bladder, which may lead to dribbling of urine
- Decreased force of urine stream
- Blood in the urine
- Hip and back pain
When the cancer has spread to other parts of the body, symptoms can include:
- Bone pain
- Weakness or paralysis caused by compression of the spinal cord
- Weight loss
- Anemia
- Kidney failure
Causes:
The
cause of prostate cancer is unknown, although it's likely that several
factors, including genetics, diet, ethnicity, hormones, and your
environment, may play a part.
Some
studies have shown a relationship between a high-fat diet and higher
testosterone levels, which stimulate growth of the prostate. Some
doctors think that testosterone replacement therapy might make existing
prostate cancer grow faster, and men who use testosterone therapy may be
more likely to develop prostate cancer than those with lower levels of
the hormone. Genes may come into play because prostate cancer tends to
happen in men who are related to one another (see "Risk Factors"
section). In addition, researchers have found a gene that is associated
with 30% of family-related prostate cancers.
Asian
men tend to have a lower incidence of prostate cancer, while
African-American men have one of the highest incidence rates in the
world.
Risk Factors:
The following factors may increase a man's risk for prostate cancer:
- Age -- prostate cancer is most common among men who are older than 55.
- Race -- African-Americans have a greater risk of developing prostate cancer than Caucasians. Caucasians have a greater risk than Native and Latin Americans.
- Family history of prostate cancer -- having a brother with prostate cancer means a man is 4.5 times more likely to develop the disease. Having a father with prostate cancer means a man is 2.3 times more likely to develop prostate cancer.
- High-fat diet -- foods rich in saturated fat may raise testosterone levels, which stimulates the growth of the prostate.
- Lack of exercise -- may increase the risk in men who eat a high-fat diet.
Diagnosis:
The
American Cancer Society recommends that men talk with their doctors
about screening tests for prostate cancer starting at age 50, or age 45
for African-American men or men with a brother or father who had
prostate cancer. Two standard tests are used for early detection of
prostate cancer:
- Digital rectal exam (DRE) -- in this test, the doctor inserts a gloved, lubricated finger into the rectum in order to feel the prostate for bumps or other abnormalities. Many malignant tumors begin in the outer part of the prostate and may be found with this exam. Some men find this test embarrassing, but it is quick, relatively painless, and helps find many prostate cancers.
- PSA test -- a blood test measuring the level of prostate-specific antigen (PSA). Prostate cancer cells produce higher amounts of PSA, so measuring PSA levels may help find cancer while it is still microscopic. However, finding elevated levels of PSA does not always mean that a man has cancer. Benign conditions such as an enlarged prostate can also elevate PSA levels.
If either the DRE or PSA test suggests that cancer might be present, your doctor may recommend the following tests:
- Transrectal ultrasound -- using a small probe inserted into the rectum, sound waves help get a visual image of the prostate.
- Biopsy of the prostate -- a tissue sample is obtained through the rectum and examined for cancerous cells.
If the biopsy shows the presence of cancer, you may need more tests to see if the cancer has spread:
- Imaging tests -- computerized tomography (CT) or magnetic resonance imaging (MRI) scans may pinpoint the location of cancer that has spread beyond the prostate.
- Bone scans and x-rays -- these tests look for spread of cancer to the bones.
- Lymph node biopsy -- a surgical procedure to find out if the cancer has spread to the lymphatic system.
Preventive Care:
The
American Cancer Society suggests men talk with their doctors about the
benefits and risks of prostate cancer screening. While the PSA test and
the DRE can find cancers early on, they usually can' t determine how
dangerous the cancer is. Some prostate cancers may grow very slowly,
while others are aggressive. Currently doctors can' t be sure who needs
treatment and who does not, meaning that some men who may not need
treatment may get it. Prostate cancer treatments can have unwanted side
effects, such as impotence and incontinence.
Studies also suggest that the following lifestyle changes may help reduce your risk of prostate cancer:
- Eating a diet low in saturated fat and rich in fruits and vegetables. Cancer-fighting foods include cruciferous vegetables (such as broccoli, cabbage, and cauliflower), those containing the antioxidant lycopene (such as tomatoes and watermelon), and other foods rich in antioxidants (such as berries).
- Exercising regularly
- Not smoking
Treatment:
There
are several options for treating prostate cancer, depending on how fast
the cancer is growing, whether it has spread, how old you are, and the
benefits and drawbacks to treatment.
If
prostate cancer is detected early, treatment usually involves either
surgical removal of the prostate or radiation therapy. For more advanced
cases of prostate cancer, or if cancer spreads beyond the prostate,
hormone medications may be used.
In
some cases, if you have only a slow-growing tumor, the doctor may
suggest "watchful waiting." Watchful waiting involves closely monitoring
the situation and giving treatment only if the man's condition worsens.
Making
changes in your diet and considering certain herbs and supplements as
supportive therapy may also help either reduce risk of prostate cancer
or make treatment more effective. If you have prostate cancer, you
should not use herbs or supplements without your doctor's supervision.
Acupuncture
can relieve pain and the side effects of surgery. Meditation and
massage may reduce stress and anxiety associated with having prostate
cancer.
Medications
Hormone
therapy or chemotherapy may be used to stop the growth of cancer cells
in the prostate. Sometimes medications are used in conjunction with
surgery or radiation, or may be used prior to surgery or radiation to
shrink large tumors. Generally they are used when prostate cancer has
spread.
Hormone therapy
lowers the body's production of testosterone or blocks its action in the
body. Lowering testosterone levels can cause tumors to shrink or slow
their growth. It is usually reserved for men whose prostate cancer has
spread. These medications include:
- Luteinizing
Hormone-Releasing Hormone (LH-RH) agonists -- LH-RH is a natural
hormone, released by the hypothalamus in the brain, that lowers the
production of testosterone. These drugs encourage the release of this
natural hormone. Side effects can include hot flashes, weight gain,
development of male breast tissue, breast pain, and nausea.
- Leuprolide (Lupron, Viadur)
- Goserelin (Zoladex)
- Buserelin (Suprefact)
- Antiandrogens
-- prevent testosterone from reaching cancer cells by blocking the
action of androgens (male sex hormones). Side effects can include
reduced sex drive, fatigue, nausea, impotence, diarrhea, and hot
flashes.
- Flutamide (Eulexin)
- Bicalutamide (Casodex)
- Nilutamide (Nilandron)
- Chemotherapy -- may reduce symptoms in men whose cancer is advanced.
Surgery and Other Procedures
- Removal of the prostate (radical prostatectomy) -- used to treat prostate cancer that has not spread beyond the prostate gland. There are two types of radical prostatectomy. In retropubic surgery, the prostate and surrounding lymph nodes are removed through an incision in the lower abdomen. In perineal surgery, the prostate is removed through an incision made between the anus and scrotum (the perineum). Side effects can include incontinence and impotence. In some cases, a technique called nerve-sparing surgery can preserve sexual function.
- Robot-assisted laparoscopic radical prostatectomy (RALRP) -- a newer procedure that uses a laparoscope, a long, thin tube with a camera, to magnify the area being removed. Smaller incisions allow a quicker healing time.
- Resection of the prostate (called TURP or transurethral resection of the prostate) -- removal of prostate tissue to relieve obstruction of urine. It is sometimes used to relieve symptoms of benign prostatic hyperplasia and may be used in men with prostate cancer who cannot have a radical prostatectomy.
- Removal of the testes (orchiectomy) -- lowers testosterone levels, but side effects can include impotence and hot flashes. Most men choose hormone therapy instead.
- Radiation -- uses radiation to kill cancer cells. There are two types of radiation therapy:
- External beam radiation therapy (EBRT or ERT) -- uses a machine to send a high-energy beam to the tumor.
- Radioactive seed implants (brachytherapy) -- places tiny radioactive seeds in the prostate to deliver radiation over a longer time period. Using irradiated seeds can lower the risk of radiation damage to organs surrounding the prostate.
Nutrition and Dietary Supplements
A
comprehensive treatment plan to support the health of men living with
prostate cancer may include a range of complementary and alternative
therapies. Preliminary studies suggest that some nutritional supplements
may reduce the symptoms of some prostate cancers or reduce your risk of
developing it. Ask your team of health care providers about the best
ways to incorporate these therapies into your overall treatment plan.
Always tell your health care provider about the herbs and supplements
you are using or considering using. Do not try to treat prostate cancer
with supplements on your own.
Follow these tips to reduce your risk of developing prostate cancer:
- Eat antioxidant foods, including fruits (such as berries, watermelon, and tomatoes) and vegetables (such as squash and bell peppers).
- Include more cruciferous vegetables (such as broccoli, cauliflower, cabbage, and Brussels sprouts) in your diet. One preliminary study suggested men who eat three or more servings a week reduced their chance of developing prostate cancer. Another study found that men who ate 28 or more servings of all kinds of vegetables per week were 35% less likely to develop prostate cancer than those who had fewer than 14 servings per week. These foods also appear to have anticancer properties in test tube studies.
- Eat more fish. Some studies show men who regularly eat fish have a lower risk of prostate cancer than those who don't eat as much fish.
- Don't eat foods high in saturated fat. High-fat diets may raise your risk of prostate cancer.
- Stay at a proper weight, and exercise regularly.
These nutrients may have cancer-fighting properties:
- Lycopene, 15 mg two times per day, is an antioxidant found in tomatoes and watermelon. In one preliminary study, men with prostate cancer either received a lycopene supplement or placebo for 3 weeks before undergoing prostate surgery. Those who received the supplement had less aggressive growth of cancer cells than those who received placebo. Lab studies have also found that lycopene inhibits the growth of prostate cancer cells in test tubes. Lycopene also appears to reduce the risk of developing prostate cancer.
- Vitamin E -- in one lab test, a specific form of vitamin E blocked the growth of prostate cancer cells. Vitamin E may also lower the risk of developing prostate cancer in men who smoke. Overall, studies on vitamin E and prostate cancer have been mixed. More research is needed to know whether vitamin E is helpful for men who already have prostate cancer.
Herbs
Herbs
are generally a safe way to strengthen and tone the body's systems. As
with any therapy, you should work with your health care provider to get
your problem diagnosed before starting any treatment. You may use herbs
as dried extracts (such as capsules, powders, and teas), glycerites
(glycerine extracts), or tinctures (alcohol extracts). Unless otherwise
indicated, you should make teas with 1 tsp. herb per cup of hot water.
Steep covered 5 - 10 minutes for leaf or flowers, and 10 - 20 minutes
for roots. Drink 2 - 4 cups per day.
- Green tea (Camellia sinensis) standardized extract, 250 - 500 mg daily, is an antioxidant that may decrease risk of cancer and heart disease. In one study, green tea extract seemed to have a slight benefit in treating some forms of prostate cancer. Use caffeine-free products. You may also make teas from the leaf of this herb.
- Saw palmetto (Serenoa repens) standardized extract, 160 mg two times daily, has been shown in some studies to help with symptoms of benign prostatic hyperplasia. It seems to have anti-androgenic effects. However, it's not clear whether saw palmetto has any effect on prostate cancer. And researchers have been concerned that saw palmetto could mask prostate cancer by lowering prostate-specific antigen (PSA) levels. However, a randomized study of more than 1,000 patients did not show this effect on PSA levels. Don' t take saw palmetto without first talking to your doctor about whether it' s right for you.
- Milk thistle (Silybum marianum) -- In one lab test, milk thistle stopped prostate cancer cells from growing. However, there is no evidence yet that it works in humans.
- Pomegranate (Punica granatum) -- In one study, men who had surgery or radiation to treat prostate cancer that had not spread and who drank 8 oz. of pomegranate juice every day slowed down the time it took their PSA levels to double. Researchers think that meant that their tumors may have not grown as fast, either. More research needs to be done. Ask your doctor before drinking pomegranate juice daily because it can interact with some medications.
- Garlic (Allium sativum), standardized extract, 400 mg two to three times daily, may help fight cancer cells, but more research is needed to know whether it's effective against prostate cancer. Garlic can interact with many medications. It may increase the risk of bleeding, particularly if you also take blood thinners such as warfarin (Coumadin) or aspirin. Ask your doctor before taking garlic.
Acupuncture
Acupuncture
may provide relief from side effects of orchiectomy, removal of the
testes. Studies also support using acupuncture to relieve pain that
often occurs when cancer has spread beyond the prostate, particularly to
the bones. A National Institutes of Health statement released in 1997
also supports the use of acupuncture to reduce nausea from chemotherapy.
Evidence
suggests acupuncture can be a valuable therapy for cancer-related
symptoms, particularly nausea and vomiting that often accompanies
chemotherapy treatment. Studies have also found that acupuncture may
help reduce pain and shortness of breath. Acupressure, or pressing on
rather than needling acupuncture points, may also help control
breathlessness and is a technique that patients can learn and then use
to treat themselves.
Massage and Physical Therapy
Studies
suggest that massage reduces stress and boosts immune function, so it
may help relieve anxiety for men being treated for prostate cancer.
Pelvic
floor exercises -- tightening and releasing muscles that start and stop
the flow of urine -- may help with incontinence caused by prostatectomy
(removal of the prostate).
Mind-Body Medicine
Meditation
Meditation may reduce stress, ease anxiety, and allow men with prostate cancer to regain a sense of self-control.
Other Considerations:
Prognosis and Complications
Most complications from prostate cancer come from specific treatments. These include:
- Prostatectomy -- can cause incontinence and impotence
- Radiation therapy -- can cause proctitis, an inflammation of the lining of the rectum; bladder infections; and impotence
- Hormone medications -- can cause loss of sex drive, impotence, hot flashes, growth of male breasts, and tenderness in male breast tissue
- Removal of testes -- can cause impotence and hot flashes
The
outlook for a man with prostate cancer depends on his age, the stage of
tumor growth, whether he has any underlying medical illnesses, and his
PSA levels. The prognosis for men with cancer that has not spread beyond
the prostate is good. Most of these cancers are curable, and after 15
years the same number of these men will be alive as those who never had
prostate cancer. If the cancer spreads beyond the prostate and does not
respond to hormone medications, however, the prognosis is poor. Still,
most prostate tumors are slow-growing, and even men with advanced
prostate cancer may survive for 5 years or more.
Alternative Names:
Cancer - prostate
- Reviewed last on: 9/28/2010
- Steven D. Ehrlich, NMD, Solutions Acupuncture, a private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network.
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