Prostate cancer is the most frequently diagnosed type of cancer in men, with the exception of skin cancer. It is also among the types of cancers that cause the most deaths in men, usually ranking after lung cancer and at a similar level to colorectal cancer in cancer deaths. However, the disease usually develops slowly and has a high survival rate when detected early. Over the past decade, survival rates have improved considerably due to earlier diagnosis and treatment.

The prostate is a walnut-size gland that is part of the male reproductive system, making fluid that is part of semen. It is located below the bladder and in front of the rectum.

The prostate generally increases in size as men age. The risk for prostate cancer also increases with age, although scientists do not know what causes prostate cancer. The slow growth of the disease in most men make it a common condition in elderly men, although not one that always requires treatment. The incidence of prostate cancer is higher in North America and Europe than other parts of the world. African American men have a higher rate than other men in the United States.

Prostate cancer in the early stages often has no symptoms. Most cases are diagnosed before symptoms appear. When symptoms are present they can be confused with signs of benign diseases. As the disease progresses, symptoms may include difficulty urinating, an urgency to urinate and pain in the pelvic region.

Two screening tools are commonly used with middle-aged and elderly men to help urologists and other physicians check for prostate cancer. These are the digital rectal exam (DRE) and a blood test called the prostate-specific antigen (PSA) test. If these tests suggest a problem, ultrasound and biopsy help in the diagnosis of prostate cancer.

Treatment options for prostate cancer vary depending on the man's age, general health and stage of the cancer. Sometimes prostate cancer is monitored but not treated (known as “watchful waiting”) because it poses little threat. Treatment of aggressive tumors and of men with more than 10 years of life expectancy can include radiation therapy, surgical removal of the gland, hormone therapy and chemotherapy if spread of the cancer is suspected. It is not clear if prostate cancer can be prevented but a healthful diet rich in vegetables and fruits and low in animal fats may help.

The American Cancer Society (ACS) estimates that nearly 219,000 new cases of prostate cancer will be diagnosed in the United States in 2007. In the same year, about 27,000 men will die from the disease. The earlier prostate cancer is diagnosed, the greater the chance for survival. More than 90 percent of all prostate cancers are diagnosed in the early stage, before they have spread to other parts of the body. The five-year survival rate for patients whose cancer is diagnosed in this early stage is nearly 100 percent. The 10-year survival rate is 93 percent and for 15 years, it is 77 percent. The survival rates have improved considerably during the past 20 years.

In American men, prostate cancer is the most common type of cancer with the exception of skin cancer. It is also one of the deadliest forms of cancer in men, ranking after lung cancer in deaths and usually with a similar number of deaths as colorectal cancers. However, most prostate cancer patients survive the disease and die of unrelated causes. Earlier detection and better treatment have increased the survival rate over recent years.

The prostate is a walnut-size gland that is part of the male reproductive system. The prostate helps produce and distribute seminal fluid, which protects sperm cells in semen. The prostate is located in front of the rectum and below the  bladder. It surrounds the  upper part of the urethra, the tube that carries urine and semen out of the body through the penis. As men age, the prostate tends to enlarge and restrict the urethra, reducing the flow of urine.

The prostate gland initially develops in the male fetus and continues to grow as the male reaches adulthood. It attains its normal size and function when increased amounts of male hormones are produced at puberty.

The prostate is a gland and nearly all prostate cancers are adenocarcinomas, meaning they begin in the glandular cells. Prostate cancer usually grows slowly. In many cases, particularly in elderly men, the disease does not require treatment, and some men are never even aware they have the disease. This is also more common in elderly men. Sometimes, however, prostate cancer grows quickly. It can spread to the hip, spine and other nearby bones and lymph nodes. It is sometimes difficult for physicians to tell which prostate cancers are dangerous and which do not pose a threat. Less than 5 percent of prostate cancers are of types other than adenocarcinomas. These other types include small cell carcinomas, squamous cell carcinomas, transitional cell carcinomas and prostate sarcomas. Cancers of these types in the prostate may not respond to treatment and usually have a poorer prognosis.

The American Cancer Society (ACS) estimates that in 2007 there will be nearly 219,000 new cases of prostate cancer in the United States. The disease accounts for 10 percent, or about 27,000 of male cancer deaths a year. About one man in six will be diagnosed with prostate cancer, but only 1 man in 34 will die of the disease. According to the ACS:

• 99 percent of men diagnosed with prostate cancer survive it at least five years
• 93 percent survive it at least 10 years
• 77 percent survive it at least 15 years

The risk of prostate cancer increases with age, especially after 50. More than 65 percent of prostate cancer is diagnosed in men over age 65, according to the Centers for Disease Control and Prevention (CDC). The median age at diagnosis is 72.

Race and nationality are also variables. African Americans have a 60 percent higher risk than white and Hispanic Americans of developing prostate cancer, and their prognosis is not as good.  Asian Americans and Pacific Islanders are at lower risk. Prostate cancer is more common in North America and northwestern Europe than in other regions of the world. Scientists do not know why the disease is more likely to affect black Americans than white Americans but less likely to affect men in Asia, Africa and South America.

Despite its high survival rate, prostate cancer presents ongoing lifestyle considerations for some patients. Any treatment of prostate cancer may affect the male genital and urinary systems. It may present complications that affect a man's ability to control his bladder, in addition to sexual functioning.

Scientists do not know what causes prostate cancer. Some think it starts with small changes that occur in the prostate gland’s structure, called prostatic intraepithelial neoplasia (PIN). PIN begins when men are in their 20s, and almost half of men have the condition by age 50. If PIN is a factor in prostate cancer, it helps explain why the risk of tumors increases with age.

Scientists cite several factors that may play a role in causing prostate cancer:

• Age. More than 65 percent of all prostate cancers are diagnosed in men over age 65 and older, according to the American Cancer Society (ACS).
  
  
• Family history. Having a brother or father who has prostate cancer more than doubles a man’s risk. If the family member developed the disease while younger, this increases the risk.
  
  
• Genetic mutations. Alterations in DNA that develop during a man’s life or are inherited from a parent and present at birth. Researchers have identified several gene mutations that make some men more prone to prostate cancer. Genetic tests for these alterations are not yet available for general use. Genetic mutations may account for 5 to 10 percent of prostate cancers, according to the Centers for Disease Control and Prevention (CDC).
  
  
• Race. African Americans have a 60 percent higher risk than white and Hispanic Americans. Asian Americans have below-average risk. Recent studies have identified several genes that occur more often in men with prostate cancer and those genes are also seen more often in African American men.
  
  
• Diet. A fatty diet rich in meat (especially red meat) and high-fat dairy appears to increase the risk.  Studies have also shown that barbecued meat produces a compound that may encourage the growth of prostate cancer cells.  Men with high cholesterol levels, particularly if they were detected before the age of 50, may have an increased risk as well.  Other studies show that men who take cholesterol-lowering medications called statins are less likely to have advanced prostate cancer. The connection is not well established, but cholesterol affects creation of testosterone, which may promote the growth of prostate cancer.
  
  
  
• Exercise. Although not conclusive, recent studies have indicated that men over the age of 65 who exercised regularly had a lower risk of prostate cancer. Lack of exercise can contribute to obesity, another factor that places a man at higher risk for the disease. In addition, studies show that obese men with prostate cancer are more likely to die from the disease than healthy weight men.
  
  
• Hormones. Studies have shown that higher levels of male hormones (androgens) may increase the risk of prostate cancer in certain men. Other hormones have been linked to a higher risk but additional research is necessary.

Many cases of prostate cancer are diagnosed before symptoms appear, through the use of a blood test called the prostate-specific antigen test (PSA). Prostate cancer usually has no symptoms in the early stages and may even lack symptoms in later stages. When symptoms are present, they often are mistaken for other conditions, such as urinary tract or bladder infections or benign enlargement of the prostate.

The prostate surrounds the urethra, the tube through which urine and semen leave the body in men. When symptoms do occur, many are related to urination. These symptoms include increased urge to urinate, weak or interrupted urine flow, pain or burning during urination, blood in the urine and the sensation that the bladder does not empty. Some men may also experience pain during ejaculation.

If the prostate cancer has metastasized (spread) to the bone, patients may have pain, especially in the hips, lower back or upper thighs.

Because prostate cancer often has no symptoms, urologists and other physicians rely on two common tests to screen for the disease. These tests may be combined for increased accuracy. Although these tests cannot prove the existence of prostate cancer, they can indicate the need for further assessment. These screening tests are:

• Digital rectal exam (DRE). The physician gently inserts a gloved, lubricated finger a few inches into the rectum and presses against the prostate to feel for nodules, hardness or other irregularities. The patient stands bent over a table or lies sideways with his knees against his chest. Most men find the DRE uncomfortable but not painful.
  
  
• Prostate-specific antigen (PSA) test. This blood test checks for PSA, a protein made in the prostate and found in the blood.  A sample of blood is drawn from the arm. Prostate cancer often raises the PSA level in blood above the normal 4 nanograms per milliliter (ng/mL). Infection, an enlarged prostate and other factors can affect PSA levels. According to the American Cancer Society (ACS):
  
  
• PSA of 4 to 10 ng/mL shows a 25 percent chance of having prostate cancer.
  
  
• PSA of more than 10 shows a 50 percent chance of having prostate cancer, with the risk rising as the PSA level grows.
  
  
Changes in the PSA, which should be tested at regular intervals, may be as significant as the absolute level. Some studies show that the changes in PSA, or PSA velocity, may provide keys to those prostate cancers that are more likely to be aggressive and require treatment.

Physicians differ on when to make the DRE and PSA test part of a man’s regular interval physical examination. Often these assessments are started around age 50 but may begin earlier for higher-risk men, such as black men or men who have a brother, father or son with prostate cancer. The DRE is less effective than the PSA in detecting prostate cancer, but in some cases it may find prostate cancer in men with low PSA levels. DRE can sometimes detect anatomic evidence for prostate cancer, which reinforces the ACS recommendation that both the DRE and PSA be used for screening. The PSA screening may not benefit men over age 75. At that age, treating a slow growing cancer may not improve a man’s life expectancy.

Depending on the results of these tests, the physician may order additional procedures:

• Transrectal ultrasound (TRUS). An ultrasound machine uses harmless sound waves to create pictures of the prostate on a video monitor. The physician picks up the sound waves through a small probe placed into the rectum. Insertion of the probe may be uncomfortable, but TRUS lasts only a few minutes.
  
  
• Biopsy. A sample of suspected tissue is taken for examination under a microscope. The most common method is core needle biopsy. Using ultrasound as a guide, the physician places a needle through the rectum into the prostate gland to extract cells. Pain is typically minimal because the procedure is performed quickly and a local anesthetic may be used. A biopsy is the definitive way to determine the type and grade of the cancer. 
  
  If biopsy detects high-grade prostatic intraepithelial neoplasia (PIN), an abnormal microscopic finding, there is a 30 to 50 percent chance of prostate cancer, according to the ACS. Men with high-level PIN are thus monitored closely and may undergo regular biopsies.

If prostate cancer is diagnosed, CAT scan, ultrasound, MRI or bone scan may be used to assess its size and track any spread to other areas. Another method to assess whether prostate cancer has metastasized is pelvic lymph node dissection, which is the surgical removal and microscopic inspection of nearby lymph nodes. This procedure may involve open surgery or laparoscopic surgery through a small incision in the abdomen. It is important to determine if, and how far, the cancer has spread because this information will influence the treatment plan and the patient's prognosis (outlook for recovery).

There are many approaches to treating prostate cancer. Factors to consider include the severity and extent of the cancer, the man’s age and general health, and whether the patient wants to risk side effects of treatment for a possible cure. Some tumors spread quickly and need aggressive therapy. Many other prostate tumors are slow growing and may not need such aggressive treatment. 

Several measurements obtained during diagnostic tests may provide some guidelines for treatment. These include the level of prostate-specific antigen and the Gleason score, a measure of the cancer’s aggressiveness. In some cases, a combination of treatments, such as surgery followed by radiation therapy, may be used as therapy.

The cure rates for radiation treatments alone and surgical removal of the prostate are similar at 10 years after treatment (about 92 percent for each treatment). Risks of aggressive treatments include the possibility of incontinence or impotence. However, prostate cancer is usually slow to spread and in some cases does not need treatment, especially in the elderly or chronically ill.

The most common treatments are:

• “Watchful waiting” (expectant management). This involves regular monitoring of the cancer through tests such as the digital rectal exam and PSA test. Watchful waiting may be used if the cancer has been detected in an early stage or if it is slow growing and confined to a small area of the prostate. It is also used with elderly patients who may not be able to tolerate cancer treatments.
  
  
• Radical prostatectomy. Surgical removal of the prostate and nearby tissues. Typically, general anesthesia is used, and the patient is discharged from the hospital after a few days. The incision may be made through the lower abdomen or the perineum, the area between the scrotum and anus. Risks of surgery include blood loss and infection. Following surgery, a narrow flexible tube (catheter) is placed through the urethra into the bladder to move urine through the penis for a few weeks while the area heals. Men usually regain full bladder control within weeks or months. This treatment often cures early prostate cancer.
  
  The potential complications for prostatectomy, which include bladder control problems and sexual dysfunction, are a major concern for most men. According to the American Academy of Family Physicians:
  
  
• Patients under age 50 are more likely to retain sexual function afterward.
  
  
• Patients over 70 are more likely to become impotent.
  
  
• Impotence is less likely if the tumor is small and nerves do not have to be cut.
  
  
• Patients rarely have severe incontinence. About one-third have occasional leaking of urine during laughter, coughing or heavy lifting.
  
  
There are a number of variations to this surgery, as well as benefits, risks and lifestyle considerations. Several studies have indicated that surgery for certain prostate cancers does not need to be performed immediately. Men who are diagnosed with early stage, low grade tumors may not have a poorer outlook for survival if surgery is delayed. However, additional research is necessary to determine the effect of delayed surgical treatment on a patient’s survival.


• Partial prostatectomy. Surgical removal of part of the prostate. The most common type of partial prostatectomy is called transurethral resection of the prostate (TURP). It is more often a treatment for an enlarged prostate, but it may be performed to relieve pain and ease urination in men with cancer that radical prostatectomy cannot cure.
  
  
• Radiation therapy. Use of high-energy x-rays or radioactive seeds to kill or shrink malignant cells. Radiation therapy is a possible option for prostate cancer that has not spread outside of the prostate gland to distant sites in the body. External beam radiation therapy (EBRT) delivers radiation from an external machine in precise doses targeted at a specific area. Internal radiation (brachytherapy) uses implanted radioactive “seeds” to deliver the radiation to the prostate or nearby areas. Radiation may be used after prostatectomy.
  
  
• Hormone therapy. Reduces the level of male hormones to control the growth of cancer. Male hormones (androgens) such as testosterone encourage the growth of many prostate tumors. Hormonal therapy may be used for early stage prostate cancer as well as for cancers that have spread in the body. Hormone therapy may be accomplished with the use of drugs or surgery. Hormone therapy cannot cure prostate cancer but can help shrink the tumor and slow the growth of the cancer.
  
  The drugs used in hormone therapy work in different ways. Some drugs, known as luteinizing hormone-releasing hormones (LH-RH) agonists, help prevent the production testosterone. Other drugs (anti-androgens) work to decrease the body’s ability to use testosterone. Patients eventually may become resistant to hormone therapy but intermittent hormone therapy programs may help the effectiveness of treatment. The side effects of hormone therapy may include breast enlargement, hot flashes, reduced sex drive and weight gain. Some of the drugs may also cause gastrointestinal problems, including nausea and diarrhea, and liver damage. Guidelines for hormone therapy are changing, both in terms of the type of hormone therapy, when to start it and the other risks associated with it. Regular patient-physician consultation about the disease and its treatment course is the best approach for hormone therapy.
  
  
• Orchiectomy (surgical castration). Surgical version of hormone therapy. This has the same effect as hormone drug therapy but is irreversible. It is usually an outpatient procedure or can involve brief hospitalization. It involves local, spinal or general anesthesia. The surgeon makes an incision in the scrotum to remove the testicles. Prosthetic testicles may be inserted to give the scrotum a normal look. Orchiectomy can cause hot flashes and will cause impotence and loss of interest in sex.
  
  
• Cryotherapy (also called cryosurgery). Freezing and destruction of prostate cancer cells. This is a newer treatment that uses liquid nitrogen to kill prostate cancer cells. In the past, poor precision with application of the treatment resulted in damage to surrounding tissues and some long-term bladder complications. New techniques now allow smaller probes and more accurate monitoring of the temperature. These advances have made cryotherapy more effective with few complications. However, additional research is necessary to determine the success of cryotherapy for prostate cancer treatment.
  
  
• Chemotherapy. Use of powerful drugs to destroy cancer cells. Chemotherapy is a less common treatment for prostate cancer than for most other types of cancer. It is sometimes used for late-stage metastatic prostate cancer that has not responded to or no longer responds to hormone therapy.

There is no way to prevent prostate cancer because there is no known cause. However, there are certain risk factors that can increase a man’s chance of developing prostate cancer. Studies have shown that dietary changes may lower the risk of the disease. Eating less meat, particularly red meat, and fat may reduce the risk. In addition, adding five servings or more of fruits and vegetables every day can reduce the risk of this cancer, as well as other diseases. 

Other studies showed that medications used to reduce cholesterol levels may decrease the risk of having advanced prostate cancer. Although not part of the study, cholesterol helps create the hormone testosterone, which may affect the growth of the cancer.

Researchers have investigated the effect of certain vitamins and supplements on prostate cancer. Some studies have indicated that a daily dose of vitamin E may lower the risk of prostate cancer. However, other studies have found it to have no impact. A large study is currently under way to evaluate the use of vitamin E and selenium to prevent prostate cancer.

Another study examined the use of the drug finasteride in lowering the risk of prostate cancer.  The study found that men taking the drug had a 25 percent lower risk of getting prostate cancer. However, those who developed the disease appeared to have cancers that were more prone to spreading. They also developed a number of side effects, including a lower sex drive and erectile dysfunction. Additional research is necessary to determine if finasteride can lower the risk of prostate cancer.

A significant amount of research has been devoted to the detection, treatment and prevention of prostate cancer. During the past decade, survival rates for the disease have significantly improved due to advances in these areas. Ongoing research for prostate cancer includes:

• Genetics. Scientists are investigating genetic tests that may help predict which men may be at higher risk for prostate cancer based on the presence of abnormal genes. Genetic research is also focusing on the chemical changes in genes that cause prostate cancer to grow. Researchers are seeking genetic clues about which cancers are most likely to spread, which could provide valuable information for the watchful waiting approach to treatment.
  
  
• Diagnostic testing. Researchers continue to investigate new methods to reliably detect prostate cancer in the early stage. A color Doppler ultrasound is a new type of test that measures blood flow in the prostate. This new ultrasound may improve the reliability of biopsies. Newer forms of the prostate specific antigen (PSA) test also may diagnose prostate cancer more accurately. Although the PSA test is useful in detecting prostate cancer, it is less effective in identifying which cases are aggressive enough to require treatment. A new test that detects early prostate cancer antigen (EPCA) may be an effective addition to the standard PSA test. The EPCA-2 test has been shown in studies to identify cancers not shown by standard PSA tests. It may also prove more useful in distinguishing aggressive cancers from those that only need monitoring. EPCA-2 is being further evaluated and shows promise for general use in the future.
  
  
• Surgical treatment. Studies continue to evaluate the timing for surgery in treating prostate cancer. Some studies have indicated that immediate surgery may not be necessary for early stage, low grade prostate cancer. Additional research is necessary in this area. Prostatectomy sometimes affects nerves in the genital area, including those that control erections, resulting in impotence.  Some surgeons are transplanting small nerves taken from the side of the foot to help prevent impotence from a prostatectomy.
  
  
• Drug treatments. Researchers continually study newer chemotherapy or combination of drugs for treatment. They are also developing new hormone therapy drugs to block the production or use of hormones in patients with prostate cancer. The use of hormone treatments in combination with other treatments continues to be studied as well. Drugs to prevent blood vessel growth (anti-angiogenesis) are being evaluated in clinical trials.
  
  
• Vaccines. Another new treatment being tested is a therapeutic vaccine for men with advanced prostate cancer. Therapeutic vaccines use the patient's cells and a protein to encourage the immune system to fight the cancer. The vaccine has shown some results in some men with advanced prostate cancer. For some patients, the vaccine increased survival time, but did not alter the time it took the tumors to return after treatment. Other potential prostate cancer vaccines are also being studied.
  
  
• Newer treatments. Researchers are evaluating a number of other treatments for early stage prostate cancer. One treatment involves destroying cancer cells by heating them with highly focused ultrasound beams. This treatment is not often performed in the United States at this time. In another treatment approach, metal rods are inserted in the prostate and the patient is placed in a magnetic field. When the rods are heated, the cancer cells are destroyed. The studies of this treatment are in the very early stage.

There are several ways of categorizing prostate cancers. These include grading systems, which indicate the degree of abnormality in cells taken in a biopsy, and staging systems, which indicate how large a tumor is and how far it has spread.

The most common grading system used with prostate cancer is the Gleason grading system. It assigns a number to both of the biggest two areas of cancer in tissue samples extracted in a biopsy. One is least aggressive, and five is most aggressive. These two grades are added to create a Gleason score.

Gleason scores rate the seriousness of the threat posed by a tumor and predict how fast it might spread:

• Low grade: 2 to 4. Slow growing tumors that are least likely to pose a threat.
  
  
• Intermediate grade: 5 to 7. Cancer that has spread to other tissues (metastasis) and is relatively less common than high grade.
  
  
• High grade: 8 to 10. Metastasis of the cancer is common.

In addition to grading systems, prostate cancers are ranked according to several staging systems. The most commonly used is the TNM Staging System. It details the extent of the primary tumor, whether the cancer has spread to nearby lymph nodes, and whether there is metastasis to distant structures.

The combination of the grading system and staging system results in a four-stage system:

• Stage I. A localized prostate tumor that cannot be felt. Less than 5 percent of a tissue sample is cancerous.
  
  
• Stage II. A localized tumor that can be felt but is limited to the prostate.
  
  
• Stage III. A regional tumor that has grown through the prostate, possibly to the seminal vesicles.
  
  
• Stage IV. Metastatic tumors that have spread beyond the prostate and seminal vesicles.

There are also other types of staging systems, such as one that uses a ranking of A, B, C or D.

Below is the five-year survival rate (percentage of men who survive prostate cancer at least five years), according to the American Cancer Society:

Preparing questions in advance can help patients have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following questions about prostate cancer:

1. How often should I be screened for prostate cancer?
   
   
2. What tests should be used for screening?
   
   
3. What additional tests will I need if an abnormality is detected in my screenings?
   
   
4. What type of prostate cancer do I have?
   
   
5. What is the grade and stage of my cancer?
   
   
6. What is my prognosis based on my cancer?
   
   
7. What are my treatment options?
   
   
8. What are the risks associated with these treatments?
   
   
9. If I need surgery, how quickly should it be performed?
   
   
10. Will I be impotent following surgery?
    
    
11. What is the likelihood that the cancer will return after treatment?
    
    
12. Does having prostate cancer place me at higher risk for other cancers?
    
    
13. Will my sons be at higher risk for prostate cancer?
    
    
14. Can you recommend support groups for prostate cancer patients and their families?