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Prostate Cancer
What is prostate cancer?
Cancers are diseases caused by the out-of-control growth of cells in the body's tissues that invade and destroy the normal cells around them. They are named for the organs or systems of the body in which they first develop, and more than 100 types of cancers have been defined. Since differing types of cancers grow at different rates and respond in their own ways to individual forms of therapy, each has its own method or methods of treatment.
As the name suggests, prostate cancer originates in the prostate, the walnut-sized male gland located at the base of the bladder and surrounding the urethra. While the role of the prostate is to produce most of the fluids found in semen, its presence results in several problems that are, obviously, unique to men including cancer, noncancerous enlargement (benign prostate hyperplasia, or BPH) and inflammation (prostatitis).
Prostate cancer is the most common cancer found in men, and is the second-leading cause of cancer deaths in men. A paradox of prostate cancer is that, while in some cases it can be an aggressive, fast-growing disease, often it is a slow-growing problem. Although it's almost a clichι, it's true that in contrast to most other cancers a man with prostate cancer is more likely to die with it than from it.
Treatment options include surgery, radiation therapy, chemotherapy, hormonal therapy and, in fact, "watchful waiting," or simply taking no action and monitoring the disease closely. Outcomes for slow-growing prostate cancers detected early and confined to the prostate itself are considered very good.
While often the prostate cancer itself may be manageable, potential side effects such as erectile dysfunction and urinary incontinence are major concerns for prostate patients. While these problems can occur, there are measures that can be taken to avoid them, and they are often only temporary.
The physicians of Connecticut Surgical Group have strong expertise in treatment of prostate cancer and have been in the forefront of medical expertise in development of techniques for treating it.
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How common is prostate cancer?
In the United States each year, nearly 190,000 men are diagnosed with prostate cancer, and approximately 32,000 men die from it, making it the most common cancer found in men, and is the second-leading cause of cancer deaths in men.
A man has just under a one-in-three chance of developing prostate cancer during his lifetime, but because it is often so slow-growing, the likelihood of dying from it is less than three percent.
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What is the anatomy of the prostate gland?
The prostate is a walnut-sized gland located at the base of the urinary bladder. It surrounds the urethra, the duct running from the bladder to the opening at the glans of the penis for the elimination of urine. Located at the base of the pelvis, it is situated just behind the pubic bone and in front of the rectum.
The role of the prostate is to produce most of the fluids that make up semen. Nerves associated with the sphincter that controls urinary flow and the corpora cavernosa of the penis (the spongy structure that fills with blood to create erections) are located close-by.
A common problem associated with the prostate gland is benign prostatic hyperplasia, or noncancerous enlargement. Such an enlargement often means growth inward to narrow the urethra channel, restricting the flow of urine. Such obstructions can also result from prostate cancer.
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What causes prostate cancer and what are the risk factors for it?
The cause or causes of prostate cancer are unclear, although it is likely there is a genetic factor, since a family history of prostate cancer reflects an increased risk for it. And worldwide demographics suggest a diet factor prostate cancer appears to be more common in nations where the diet includes a higher level of fat (but these are also nations where screening for prostate cancer is likely to be more effective and mortality from other diseases is lower).
Aging is a prominent risk factor for prostate cancer. It's estimated that for American men under 40 the risk of developing it is only one in 10,000; for those ages 40 to 59, it's about one in 55; and for those 60 and over it's about one in eight.
Race and ethnicity are also factors in your risk for prostate cancer. Afro-American men are at greatest risk (about 224 cases per 100,000 men). The risk for Caucasian American men is about 150 cases per 100,000 men, and among Asians it's about 82 cases per 100,000 men.
If you have a family history of prostate cancer, your risk is increased from a factor of two to 11 times, depending on your family's experience. For example, if your father and a brother developed it before the age of 50, your risk is increased by about seven times. If only one relative has had it but didn't develop it until after age 70, your risk of developing it through a genetic factor is probably small.
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What are the symptoms of prostate cancer?
Stating the symptoms of prostate cancer is problematical for two reasons. One is that in its early stages, it usually doesn't cause any symptoms. The other is that symptoms that do appear can also reflect other problems, such as benign prostate hyperplasia, prostatitis and urinary tract infection. Most cases of prostate cancer that are detected in the early stages are usually done so because of regular screening tests.
When symptoms do occur, they are likely to include any of the following:
- Difficulty beginning urination
- Weak urine stream
- Frequent urination and a feeling that your bladder isn't empty
- Pain or a burning feeling during urination
- Blood in the urine (or in semen)
- Painful ejaculation
- Dull pain in the pelvic area
- General pain in the lower back, hips or upper thighs
- Loss of appetite
- Unexplained weight loss
- Pain in your bones
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How is prostate cancer screened for?
The two basic screening tools for prostate cancer are digital rectal examination (DRE) and measurement of prostate specific antigen (PSA) in your blood. Neither test carries an iron-clad guarantee other conditions (especially BPH) can present the same symptoms but they can alert your physician to the need for additional tests. While a PSA test can give a false negative, normal results from both PSA and DRE tests can represent pretty good assurance that prostate cancer is not present.
If your race, ethnicity or family history places you at high risk, organizations such as the American Cancer Society usually recommend that you be screened regularly beginning at age 40. Otherwise, it's usually recommended that men be screened beginning at age 50.
- Digital Rectal Examination. Since the prostate is located directly adjacent to the rectum, digital rectal examination lets your doctor physically feel your prostate for abnormalities in size, texture or shape with a gloved, lubricated finger.
- Prostate Specific Antigen. Prostate specific antigen is a substance produced by the prostate gland that is normally confined within the gland. While a certain level of PSA invariably escapes into the bloodstream, elevated levels may be present in the blood due to cancer or BPH, inflammation or infection. Thus, while an elevated level of PSA in a blood sample may not necessarily indicate the presence of cancer, it may suggest the need for additional testing.
Your level of PSA is measured in nanograms of PSA per milliliter of blood (ng/ml). Generally, a rating of less that 4 ng/ml is normal. A rating between 4 ng/ml and 10 ng/ml is generally considered a medium elevation and more than 10 ng/ml is high.
It should be noted that while positive results for either DRE or PSA screening cannot be ignored, they are far more likely to indicate the presence of a benign condition than of cancer.
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How is prostate cancer diagnosed?
If your DRE or PSA testing indicated the possibility of prostate cancer, your doctor will probably order other tests. These may include:
- Urinalysis. While this test doesn't diagnose prostate cancer, it can help in identifying or ruling out other factors that may have produced the DRE or PSA results.
- Transrectal ultrasound. This test uses a small ultrasound probe inserted into your rectum and adjacent to the prostate to use sound waves to obtain an image of your prostate gland and any abnormalities that may be detectable (not all are).
- Prostate Biopsy. A prostate biopsy is a procedure to capture small samples of tissue from the gland for analysis. The test is usually performed with the guidance of transrectal ultrasound, using a spring-loaded device attached to the ultrasound probe. The device allows samples to be taken from various areas of the gland, each about Ύ of an inch long and 1/16 of an inch wide.
Once samples are obtained, they are analyzed by a pathologist to determine if cancer is present. The results are usually available within 48 to 72 hours.
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What is grading?
Grading is a system of describing whether malignant cells that have been found represent a slow-growing or fast-growing form of cancer. Cancerous cells from a sample are compared with normal prostate cells to determine their "aggression level" the more different they are, the more likely the cancer is to spread quickly.
By studying size and shape, the pathologist is usually able to predict the nature of the cancer involved, important information in determining appropriate treatment options.
Cancers are usually graded on a range of two to 10, with scores below four representing low aggressiveness and above eight high aggressiveness.
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What is staging?
Staging is a method of describing how extensively the cancer has spread, from still confined within the prostate gland to spread to lymph nodes, bones and other organs. The stage a cancer has reached plays a large part in determining how it should be treated.
Prostate cancer is categorized in four stages:
- Stage I The cancer cannot be felt by a digital rectal examination and is still confined to the prostate gland.
- Stage II The cancer can be felt during a DRE but appears to still be confined to the gland.
- Stage III The cancer has spread beyond the prostate to the seminal vesicles, the bladder or other nearby tissues.
- Stage IV The cancer has spread to the lymph nodes, bones or other organs.
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What other tests may be ordered?
Generally, prostate cancer is localized and no further tests are necessary. At times, however, it is necessary to determine if the cancer has spread from the prostate to other tissue and additional tests may be ordered. Usually, prostate cancer spreads first to the lymph nodes and bones.
- To evaluate the lymph nodes, a lymph node biopsy may be ordered. Lymph vessels are ducts that carry the clear fluid called lymph the watery fluid that carries tissue waste and immune-system cells throughout the body between lymph-nodes, or bean-sized glands. By removing and analyzing nodes near the prostate, it can be determined whether the cancer has spread that far. While a positive analysis will likely make additional testing or more extensive treatment necessary, a negative result can provide assurance that the cancer has not spread.
- To determine whether cancer has spread to your bones, a bone scan using a very short-lived radioactive isotope may be ordered. In this test, which is equivalent in radiation to a standard x-ray, the isotope will be absorbed by cancer cells and the radiation emanating from your bones will be captured by a gamma camera to give doctors a means of detecting and defining malignant tissue within your bones.
- Computerized tomographic (CT) scans or magnetic resonance (MRI) scans may be ordered to provide additional information about your lymph nodes and other tissues.
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What are the treatments for prostate cancer?
Treatment options for prostate cancer can range from watchful waiting to total removal of the prostate gland radical prostatectomy. Options in between include hormone therapy, chemotherapy, external beam radiation therapy, radioactive seed implant treatment (brachytherapy) and the surgical procedure orchiectomy. Each has its benefits and drawbacks. In some cases, a combination of therapies may be appropriate.
To some extent, outcomes depend on expectations, both medical and psychological. Erectile dysfunction (or impotence) and urinary incontinence are potential side effects of treatment because the nerves that support these functions are easily damaged.
- Radical prostatectomy. Surgery to totally remove the diseased prostate gland will offer some patients the best outcomes medically. It's most appropriate for cases in which the cancer is still confined to the gland itself.
- Radiation therapy. Radiation therapy, in which the prostate is not removed but treated in place with ionizing radiation, may be appropriate for cancers that have extended beyond the prostate gland itself into nearby tissues.
- Cryoablation. Cryoablation is the use of controlled freezing to destroy cancerous cells and slow the growth of any cancer that remains.
- Chemotherapy. At the time being chemotherapy is generally not viewed as an especially effective treatment against prostate cancer itself, although new chemical agents are under investigation. And, chemotherapy may be used for other problems associated with prostate cancer such as cancer that has spread to other tissues.
- Hormone therapy. Since male hormones such as testosterone play a major role in prostate cancer growth, hormone therapy seeks to suppress the production of these substances in order to slow the cancer's progress or even cause the tumor to shrink.
- Orchiectomy. Since the testicles are responsible for as much as 95 percent of the body's testosterone production, another option for reducing testosterone's influence in the body is orchiectomy, the surgical removal of the testicles.
- Watchful waiting. Watchful waiting, in effect, means taking no action and monitoring the progress of the disease. In cases in which the cancer is of a slow-growing variety, this may be sufficient.
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What should I think about in terms of the best treatment options for me?
Considerations as to which approach is most appropriate for you requires serious discussion between you and your doctor. Each case is different, and factors in the choice include such issues as the grade and stage of your cancer, your age, your overall health and psychological and lifestyle concerns.
Surgery, for example, may be more appropriate for a cancer that is confined to the prostate than for a case in which the cancer has spread to other areas. And it may be considered more important for a man in his 50s who might otherwise have to live for decades with prostate cancer rather than for one in his 70s whose shorter life expectancy would make his slow-growing prostate cancer a less-significant issue.
Men who are accustomed to an active athletic or outdoor life may deem it more important to minimize the risk of incontinence than to undergo surgery that increases the risk of this side effect. And, some men may find it psychologically unacceptable to undergo removal of their testicles.
It also should be noted that usually any impotence and incontinence that result from treatment are only temporary, and normal functioning is often regained. By and large, age and overall health play a role in these outcomes, and therapies (such as exercises to strengthen pelvic muscles) exist to help in recovery. A younger man, or one who experienced good sexual function before his treatment, for example, is more likely to retain or regain normal function after treatment.
As to incontinence, some 95 percent of men regain normal function. Incontinence often shows up as stress incontinence a tendency to lose bladder control when sneezing, coughing or lifting heavy objects.
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What is radical prostatectomy?
Radical prostatectomy is surgery to totally remove the prostate gland. Generally, radical prostatectomy is most appropriate for cases in which the cancer is still confined to the prostate gland Stages I and II or only minimally extended beyond it.
In this procedure, your surgeon will use special nerve-sparing techniques, working carefully to remove your prostate and nearby lymph nodes while preserving muscles and nerves associated with sexual function and urination.
Your surgeon will use one of several techniques.
- In the more commonly used retropubic approach, the prostate is removed through an incision in your lower abdomen. Its advantage is that adjacent lymph nodes can be removed for examination in the same procedure.
- The perineal approach involves an incision in the base of your pelvis between the anus and the base of the penis. The advantages of this technique are that it involves less bleeding and pain and shorter hospitalization and recovery time. However, excision of lymph nodes for analysis requires a separate procedure. In recent years, some doctors have begun performing a minimally invasive laparoscopic procedure to retrieve lymph nodes prior to the prostatectomy procedure, with negative biopsy results clearing the way for the perineal option.
- Robotic and laparoscopic prostatectomy involve removal of the prostate and adjacent lymph nodes with minimally invasive surgical techniques, using fiber-optic instruments inserted through several tiny incisions rather than a long open incision.
Any of these can be done with or without nerve-sparing techniques designed to preserve sexual function and urinary continence. The consideration is that nerve-sparing surgery may not be feasible when the cancer clearly has extended outside the prostate gland and it is necessary to remove adjacent tissue and nerve fibers as well.
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What is TURP?
If your cancer is growing in such a way that it may obstruct the flow of urine through your urethra, you may encounter a surgical procedure called transurethral resection of the prostate (TURP). TURP is commonly performed to deal with BPH (the benign enlargement of the prostate), and its use for prostate cancer is basically to eliminate an obstruction, not to cure the cancer. In fact, it is not unusual for a patient's prostate cancer to be discovered during a TURP procedure for BPH.
The procedure involves excision of both cancerous and normal tissue, but usually does not involve removing all the cancer. Nor does it usually remove all of the prostate gland. Unlike prostatectomy, TURP is typically performed through a catheter inserted into the urethra, shaving the prostate from within the urethra to restore the channel for the flow of urine.
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What is external beam radiation therapy?
External beam radiation is the use of high speed linear accelerators to focus powerful beams of radiation energy on cancerous tissue within your body. Radiation therapy may be appropriate for some localized cancers. Age, grade and stage of tumors will affect this decision.
External beam radiation may be used as a primary treatment, or it may be used following prostatectomy to seek to ensure that any remaining cancer cells are destroyed.
External beam radiation usually is provided once a day, five days a week for eight weeks. Each session takes about 15 minutes, although the radiation application itself usually lasts only about a minute.
The treatment is non-invasive and involves minimal discomfort. However, as with surgery, external beam radiation carries with it a risk of side effects involving sexual function and urinary continence. While it doesn't usually appear immediately after treatment, erectile dysfunction can emerge gradually due to nerve and artery damage. It's estimated that about half of men who had normal sexual function prior to treatment retain it.
As for urinary continence, in addition to nerve damage external beam radiation can cause narrowing of the urethra, making urination difficult. However, most patients gradually recover urinary control.
An additional side effect of radiation therapy may be bowel difficulties, such as diarrhea, rectal bleeding and discomfort. Usually, these disappear over time.
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What is brachytherapy?
Brachytherapy is a technique of radiation therapy that uses tiny radioactive pellets or "seeds" placed directly within the prostate gland rather than relying on external beam radiation. The advantage of this approach compared to external beam treatment is that it places the maximum radiation effect immediately adjacent to the cancerous tissue with less extensive side effects on surrounding normal tissue.
Doctors have access to two different varieties of prostate brachytherapy low dose rate and high dose rate versions, describing the radioactivity strength of the seeds.
In low dose rate brachytherapy, as many as 200 tiny seeds are placed within the prostate and left there permanently to do their work over an extended period. This is the more commonly performed version. Placement of the seeds is performed under ultrasound guidance, with the patient asleep under general anesthesia. The radioactivity of the seeds diminishes over a period of months following the implantation and usually disappears in about a year (it is not necessary to remove the seeds after that has happened).
In high dose rate seed implantation, the higher-strength radioactive seeds are placed for short periods and then removed. Thin, hollow catheters are placed into the prostate under ultrasound guidance, making it possible for the higher-strength seeds to be inserted and removed, usually in two to three sessions over a period of days. The seeds are inserted by means of a remote-control device that can move the seeds into different locations within the catheter to maximize therapeutic effect. Once the treatment is finished and the seeds will no longer be inserted, the catheters are removed.
Although bowel difficulties can occur as side effects of brachytherapy, they are usually less severe than with external beam radiation. Erectile dysfunction generally affects between 30 and 50 percent of brachytherapy patients. Since the urethra incurs higher doses of radiation than with external beam therapy, nearly all men experience some urinary difficulties, including complete urinary obstruction. However, most urinary problems gradually subside over time.
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What is cryoablation?
Cryoablation is the technique of freezing the prostate gland to destroy cancer cells. Controlled freezing can damage both the tissue at the molecular and cellular levels and the connective tissues and capillaries that supply blood to the area, thus slowing any growth of the cancer.
Cryoablation is performed with probes placed at predetermined sites throughout the prostate, placed under ultrasound guidance. Care is taken not to freeze the urethral area in order to minimize the risk of incontinence. The procedure is performed with an overnight stay in the hospital, usually with a temporary catheter left in place to empty the bladder for about two weeks.
While incontinence is a relatively rare side effect of cryoablation, erectile dysfunction is relatively common. A risk of the procedure is the possibility of urinary rectal fistula creation of a channel between the prostate or bladder and the rectum. This can result in diarrhea caused by urine entering the rectum, or infection from bacteria in the bladder.
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What is hormone therapy?
Since the body's natural androgens hormones such as testosterone have been clearly identified as substances that promote prostate cancer's growth, therapy that seeks to suppress those hormone's production is a significant option for prostate cancer patients, especially in cases in which the cancer is somewhat advanced.
This is most often done through the use of lutenizing hormone-releasing hormone agonists (LH-RH) that prevent the testicles from receiving messages from the hypothalamus in the brain to produce testosterone. For this purpose, the LH-RH agents are injected every three months. With testosterone depleted, prostate cancer tissues may shrink by as much as 90 percent in advanced cases.
It's important to emphasize that hormone therapy can shrink prostate cancer, but it does not cure the disease. And it remains effective for two to three years, after which the body appears to find a way to resume it's testosterone production. Because of this, many doctors follow a program of intermittent hormone therapy, using LH-RH when PSA levels rise above 10 and suspending their use when it drops. And, in fact, LH-RH therapy may be used for patients who are scheduled for radiation therapy in order to shrink tumors before the radiation treatments are begun.
Production of testosterone by the testicles accounts for 90 to 95 percent of the body's supply of the hormone. The balance comes from the adrenal glands. Since this source is not blocked by LH-RH, a different approach is used to deal with the five to 10 percent remaining. Drugs called anti-androgens are used to block the action of testosterone on cancer cells.
It should be noted that side effects of hormone therapy can include anemia, impotence, hot flashes, swollen breasts, loss of muscle and bone mass and weight gain.
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What is orchiectomy?
Orchiectomy is a procedure to control testosterone production by surgically removing the testicles. As with hormone therapy, the goal is to eliminate a natural substance in the body that plays a large role in prostate cancer's growth.
As with hormone therapy, it doesn't cure the cancer, but is a measure to curtail its growth. Most often, it is done in cases in which the cancer is advanced with the goal of reducing or eliminating pain.
Side effects are similar to those of hormone therapy, possibly including anemia, impotence, hot flashes, swollen breasts, loss of muscle and bone mass and weight gain.
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What is watchful waiting?
Watchful waiting simply means taking no action to deal with cases of prostate cancer that are detected at an early stage, when symptoms and complications are not a factor. The goal here is to use digital rectal examinations, PSA testing and biopsies to monitor the progress of the disease.
As noted, many prostate cancers are slow-growing in nature. It's perfectly possible that many men, especially older men, will be able to live their lives and die with prostate cancer rather than from it.
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What can I do to lower my risk of prostate cancer?
There isn't any way to prevent prostate cancer, but there are measures you can take to reduce your risk for it, or to slow its development. These include following a healthy diet, keeping physically fit and being vigilant about being screened for it.
- Healthy diet. Avoid high-fat foods a diet high in fat has been demonstrated to be linked to prostate cancer. Emphasizing fruits, vegetables and whole-grain foods will benefit your health in many ways, including reducing your risk of prostate cancer.
Foods containing the antioxidant lycopene may be especially beneficial lycopene has been shown to work against prostate cancer. Foods with lycopene include tomatoes especially cooked tomato sauces. Foods containing soy products may be beneficial in controlling testosterone.
Some cancer specialists have also expressed some interest in the use of Selenium and Vitamin E for prostate cancer prevention, but proof of there effectiveness is still not available.
- Keeping Physically Fit. A regular program of exercise has been clearly demonstrated to have many benefits. As far as cancer goes, it may strengthen the immune system and improve digestion two factors that may help your body resist disease's development.
- Screening. As noted, since prostate cancer doesn't show symptoms in its early stages, regular screening in the form of a doctor's digital rectal examination and PSA testing are important steps you can take to catch prostate cancer early when it is most treatable.
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For additional information
You can find additional information about prostate cancer at web sites sponsored by government agencies, societies and healthcare institutions. It should perhaps be noted that the World Wide Web is open to many sources posting questionable information and promises, and you are encouraged to seek information from established, reputable organizations.
Likely sources include:
The American Cancer Society
www.cancer.org
American Urological Association Health Guide
www.urologyhealth.org
National Cancer Institute
www.nci.nih.org
National Prostate Cancer Coalition
www.pcacoalition/org
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