Table of contents
What is prostate cancer?
Prostate cancer is a disease in which malignant (cancer) cells form in the tissues of the prostate. The prostate is a gland in the male reproductive system. It lies just below the bladder (the organ that colelcts and empties urine) and infront of the rectum (the lower part of the intestine). It is about the size of a walnut and surrounds part of the urethra (the tube that empties urine from the bladder). The prostate gland makes fluid that is part of the semen. Prostate cancer is found mainly in odler men. In the U.S., about 1 out of 5 men will be diagnosed with prostate cancer.
What are signs and symptoms of prostate cancer?
These and other signs and symptoms may be caused by prostate cancer or by other conditions. Check with your doctor if you have any of the following:
Weak or interrupted ("stop-and-go") flow of urine.
Sudden urge to urinate
Frequent urination (especially at night)
Trouble starting the flow of urine.
Trouble emptying the bladder completely.
Pain or burning while urinating.
Blood in the urine or semen.
A pain in the back, hips, or pelvis that doesn't go away.
Shortness of breath, feeling very tired, fast heartbeat, dizziness, or pale skin caused by anemia.
Weak urine flow/stream
Other conditions may cause the same symptoms. As men age, the prostate may get bigger and block the urethra or bladder. This may cause trouble urinating or sexual problems. The condition is called benign prostatic hyperplasia (BPH), and although it is not cancer, surgery may be needed. The symptoms of benign prostatic hyperplasia or of other problems in the prostate may be like symptoms of prostate cancer.
Note: Many people who have prostate cancer may not have any signs or symptoms at all. Therefore if you have a family history of prostate cancer or if you are African American, you should discuss with your healthcare provider about when you should start having blood tests (PSA) and a digital rectal exam done to see if you have prostate cancer.
What tests are used to detect and diagnose prostate cancer?
The following tests and procedures may be used:
History and Physical Exam (H&P): A history of the patient’s health habits and past illnesses and treatments will be taken. A family history of prostate cancer or being African American are risk factors for prostate cancer. A body exam is also done to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual.
Digital rectal exam (DRE): An exam of the rectum. The doctor or healthcare provider inserts a lubricated, gloved finger into the rectum and feels the prostate through the rectal wall for lumps or abnormal areas.
Prostate-specific antigen (PSA) test: A test that measures the level of PSA in the blood. PSA is a substance made by the prostate that may be found in an increased amount in the blood of men who have prostate cancer. PSA levels may also be high in men who have an infection or inflammation of the prostate, BPH (an enlarged, but noncancerous, prostate), in patients who have a catheter (tube) in the penis, or patients who have had recent surgery in the prostate or bladder.
Tips: To have an accurate reading of the PSA test, you should not have sex for 3 days before or any bicycle activity prior to having the test done.
Transrectal ultrasound or sonogram: A procedure in which a probe that is about the size of a finger is inserted into the rectum to check the prostate. The probe is used to bounce high-energy sound waves (ultrasound) off internal tissues or organs and make echoes. The echoes form a picture of body tissues called a sonogram. Transrectal ultrasound may be used during a biopsy procedure.
Magnetic resonance imaging (MRI): A procedure that uses a strong magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. Some MRIs also use a transrectal probe. A probe that gives off radio waves is inserted into the rectum near the prostate. This helps the MRI machine make clearer pictures of the prostate and nearby tissue. A transrectal MRI is done to find out if there are areas suspicious for cancer in the prostate or if the cancer has spread outside the prostate into nearby tissues.
Biopsy: The removal of cells or tissues so they can be viewed under a microscope by a pathologist, a doctor who specializes in looking at tissue under a microscope to see if it is cancer or not. The pathologist will check the tissue sample to see if there are cancer cells and find out the Gleason score. The Gleason score ranges from 2-10 and describes how aggressive the cancer is and how likely it is that a tumor will spread. The lower the number, the less aggressive the cancer and the less likely the tumor is to spread. A transrectal biopsy is used to diagnose prostate cancer. A transrectal biopsy is the removal of tissue from the prostate by inserting a thin needle through the rectum and into the prostate. This procedure is usually done using transrectal ultrasound (TRUS) to help guide where samples of tissue are taken from.
What factors affect prognosis (chance of recovery) and treatment options?
The prognosis (chance of recovery) and treatment options depend on the following:
The stage of the cancer (level of PSA, Gleason score, grade of the tumor, how much of the prostate is affected by the cancer, and whether the cancer has spread to other places in the body).
The patient’s age.
Whether the cancer has just been diagnosed or has recurred (come back).
Treatment options also may depend on the following:
Whether the patient has other health problems.
The expected side effects of treatment.
Past treatment for prostate cancer.
The wishes of the patient.
What are the Stages of Prostate Cancer?
After prostate cancer has been diagnosed, tests are done to find out if cancer cells have spread outside the prostate or to other parts of the body.
The process used to find out if cancer has spread outside the prostate or to other parts of the body is called staging. The information gathered from the staging process determines the stage of the disease.
The following tests and procedures also may be used in the staging process:
Bone scan: A test to check if there is cancer in the bone. A very small amount of radioactive material is injected into a vein and travels through the bloodstream. The radioactive material collects in the bones and is detected by a scanner.
MRI (magnetic resonance imaging): A test that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. MRI does not involve radiation.
CT scan (CAT scan): A test that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography. CT involves radiation (X-Rays).
Pelvic lymphadenectomy : A surgical procedure to remove the lymph nodes in the pelvis. A pathologistviews the tissue under a microscope to look for cancer cells.
Seminal vesicle biopsy : The removal of tissue from the seminal vesicles (glands that make semen) using a needle. A pathologist views the fluid under a microscope to look for cancer cells.
ProstaScint scan: A test to find out if cancer that has spread from the prostate to other parts of the body, such as the lymph nodes. A very small amount of radioactive material is injected into a vein and travels through the bloodstream. The radioactive material attaches to prostate cancer cells and is detected by a scanner. The radioactive material shows up as a bright spot on the picture in areas where there are a lot of prostate cancer cells.
The stage of the cancer is based on the results of the staging and diagnostic tests, including the prostate-specific antigen (PSA) test and the Gleason score. The tissue samples removed during the biopsy are used to find out the Gleason score. The Gleason score ranges from 2-10 and describes how different the cancer cells look from normal cells and how likely it is that the tumor will spread. The lower the number, the less likely the tumor is to spread.
How does cancer spread to the rest of the body?
Cancer can spread through tissue, the lymph system, and the blood:
Tissue.
The cancer spreads from where it began by growing into nearby areas.
Lymph system.
The cancer spreads from where it began by getting into the lymph system. The cancer travels through the lymph vessels to other parts of the body.
Blood.
The cancer spreads from where it began by getting into the blood. The cancer travels through the blood vessels to other parts of the body
Cancer may spread from where it began to other parts of the body.
When cancer spreads to another part of the body, it is called metastasis. Cancer cells break away from where they began (the primary tumor) and travel through the lymph system or blood.
Lymph system. The cancer gets into the lymph system, travels through the lymph vessels, and forms a tumor (metastatic tumor) in another part of the body.
Blood. The cancer gets into the blood, travels through the blood vessels, and forms a tumor (metastatic tumor) in another part of the body.
The metastatic tumor is the same type of cancer as the primary tumor. For example, if prostate cancer spreads to the bone, the cancer cells in the bone are actually prostate cancer cells. The disease is metastatic prostate cancer, not bone cancer. Denosumab, a monoclonal antibody, may be used to prevent bone metastases.
What stages are used for prostate cancer?
The following stages are used for prostate cancer:
The TNM (tumor, nodes, metastasis) staging system is used to describe a cancer’s clinical stage, or how far it has spread. The system gives a T number (T1 to T4) to describe the extent of the tumor as felt during a digital rectal exam (DRE). The N number (N0 to N1) shows whether the cancer has spread to any lymph nodes, and the M number (M0 to M1) shows the presence or absence of metastasis (spread to distant sites). The T and M designations are divided into subcategories. The TNM staging system is used to help guide appropriate prostate cancer treatment options.
T1: The tumor cannot be palpated (felt) during a digital rectal exam or seen with diagnostic imaging
T1a: Tumor found incidentally during surgery (TURP) for benign prostatic hyperplasia (BPH) and is present in less than 5% of removed tissue
T1b: Tumor found incidentally during BPH surgery (TURP) but involves more than 5% of removed tissue
T1c: Tumor found during needle biopsy for elevated PSA
T2: Tumor can be palpated (felt) during DRE but is believed to be confined to the gland
T2a: Tumor involves one-half or less of one side of the prostate
T2b: Tumor involves more than one-half of one side but not both sides
T2c: Tumor involves both sides of the prostate
T3: Tumor extends through the prostate capsule and may involve the seminal vesicles
T3a: Tumor extends through the capsule but does not involve the seminal vesicles
T3b: Tumor has spread to the seminal vesicles
T4: Tumor has invaded adjacent structures (other than the seminal vesicles), such as the bladder neck, rectum or pelvic wall N0: Cancer has not spread to any lymph nodes N1: Cancer has spread to one or more regional lymph nodes (nodes in the pelvic region) M0: No distant metastasis M1: Distant metastasis
M1a: Cancer has spread to distant lymph nodes
M1b: Cancer has spread to the bones
M1c: Cancer has spread to other organs, with or without bone involvement
Treatment options
What treatment options are available for prostate cancer?
Different types of treatment are available for patients with prostate cancer. Some treatments are standard (the currently used treatment), and some are being tested in clinical trials. A treatment clinical trial is a research study meant to help improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment. Patients may want to think about taking part in a clinical trial. Some clinical trials are open only to patients who have not started treatment.
Types of Standard Prostate Treatment
In some cases, nerve-sparing surgery can be done. This type of surgery may save the nerves that control erection. However, men with large tumors or tumors that are very close to the nerves may not be able to have this surgery.
1.Watchful waiting or active surveillance:
Watchful waiting and active surveillance are treatments used for older men who do not have signs or symptoms or have other medical conditions and for men whose prostate cancer is found during a screening test
Watchful waiting is closely monitoring a patient’s condition without giving any treatment until signs or symptoms appear or change. Treatment is given to relieve symptoms and improve quality of life
Active surveillance is closely following a patient's condition without giving any treatment unless there are changes in test results. It is used to find early signs that the condition is getting worse. In active surveillance, patients are given certain exams and tests, including digital rectal exam, PSA test, transrectal ultrasound, and transrectal needle biopsy, to check if the cancer is growing. When the cancer begins to grow, treatment is given to cure the cancer.
Oberservation, watch and wait, and expectant management are other terms used to describe when treatment is not given to cure prostate cancer after diagnosis
2. Surgery
Patients in good health whose tumor is in the prostate gland only may be treated with surgery to remove the tumor. The following types of surgery are used:
Radical prostatectomy: A surgical procedure to remove the prostate, surrounding tissue, and seminal vesicles.
Retropubic prostatectomy: This is an open surgery (unlike the robotic surgery mentioned below). Here, a surgical procedure to remove the prostate through an incision (cut) in the abdominal wall. Removal of nearby lymph nodes may be done at the same time.
Perineal prostatectomy: A surgical procedure to remove the prostate through an incision (cut) made in the perineum (area between the scrotum and anus). Nearby lymph nodes may also be removed through a separate incision in the abdomen.
Robot assisted laparoscopic radical prostatectomy: This surgery is similar to retropubic prostatectomy but it is done using a robot through several small incisions.
Pelvic lymphadenectomy: A surgical procedure to remove the lymph nodes in the pelvis. A pathologist views the tissue under a microscope to look for cancer cells. If the lymph nodes contain cancer, the doctor will not remove the prostate and may recommend other treatment.
Transurethral resection of the prostate (TURP): A surgical procedure to remove tissue from the prostate using a resectoscope (a thin, lighted tube with a cutting tool) inserted through the urethra. This procedure is done to treat benign prostatic hypertrophy and it is sometimes done to relieve symptoms caused by a tumor before other cancer treatment is given. TURP may also be done in men whose tumor is in the prostate only and who cannot have a radical prostatectomy.
In some cases, nerve-sparing surgery can be done. This type of surgery may save the nerves that control erection. However, men with large tumors or tumors that are very close to the nerves may not be able to have this surgery.
Possible problems after prostate cancer surgery include the following:
Impotence.
Leakage of urine from the bladder or stool from the rectum.
Shortening of the penis (1 to 2 centimeters). The exact reason for this is not known.
Inguinal hernia (bulging of fat or part of the small intestine through weak muscles into the groin). Inguinal hernia may occur more often in men treated with radical prostatectomy than in men who have some other types of prostate surgery, radiation therapy, or prostate biopsy alone. It is most likely to occur within the first 2 years after radical prostatectomy.
3. Radiation therapy
Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing.
There are different types of radiation therapy:
External radiation therapy uses a machine outside the body to send radiation toward the cancer. Conformal radiation is a type of external radiation therapy that uses a computer to create a 3-dimensional(3-D) picture of the tumor. The radiation beams are shaped to fit the tumor.
Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer. In early-stage prostate cancer, the radioactive seeds are placed in the prostate using needles that are inserted through the skin between the scrotum and rectum. The placement of the radioactive seeds in the prostate is guided by images from transrectal ultrasound or computed tomography (CT). The needles are removed after the radioactive seeds are placed in the prostate.
Alpha emitter radiation therapy uses a radioactive substance to treat prostate cancer that has spread to the bone. A radioactive substance called radium-223 is injected into a vein and travels through the bloodstream. The radium-223 collects in areas of bone with cancer and kills the cancer cells.
The way the radiation therapy is given depends on the type and stage of the cancer being treated. Men treated with radiation therapy for prostate cancer have an increased risk of having bladder and/or gastrointestinal cancer.
Radiation therapy can cause impotence and urinary problems.
4. Cryosurgery
Cryosurgery is a treatment that uses an instrument to freeze and destroy prostate cancer cells. Ultrasound is used to find the area that will be treated. This type of treatment is also called cryotherapy. Cryosurgery can cause impotence and leakage of urine from the bladder or stool from the rectum.
5. Proton beam radiation therapy
Proton beam radiation therapy is a type of high-energy, external radiation therapy that targets tumors with streams of protons (small, positively charged particles).
6. Hormone therapy
Hormone therapy is a cancer treatment that removes hormones or blocks their action and stops cancer cells from growing. Hormones are substances made by glands in the body and circulated in the bloodstream. In prostate cancer, male sex hormones can cause prostate cancer to grow. Drugs, surgery, or other hormones are used to reduce the amount of male hormones or block them from working. Hormone therapy for prostate cancer may include the following:
Luteinizing hormone-releasing hormone agonists can stop the testicles from making testosterone. Examples are leuprolide, goserelin, and buserelin.
Antiandrogens can block the action of androgens (hormones that promote male sex characteristics), such as testosterone. Examples are flutamide, bicalutamide, enzalutamide, and nilutamide.
Drugs that can prevent the adrenal glands from making androgens include ketoconazole and aminoglutethimide.
Orchiectomy is a surgical procedure to remove one or both testicles, the main source of male hormones, such as testosterone, to decrease the amount of hormone being made.
Estrogens (hormones that promote female sex characteristics) can prevent the testicles from making testosterone. However, estrogens are seldom used today in the treatment of prostate cancer because of the risk of serious side effects.
Hot flashes, impaired sexual function, loss of desire for sex, and weakened bones may occur in men treated with hormone therapy. Other side effects include diarrhea, nausea, and itching.
7. Chemotherapy
Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is placed directly into the cerebrospinal fluid, an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas (regional chemotherapy). The way the chemotherapy is given depends on the type and stage of the cancer being treated.
8. Biologic therapy
Biologic therapy is a treatment that uses the patient’s immune system to fight cancer. Substances made by the body or made in a laboratory are used to boost, direct, or restore the body’s natural defenses against cancer. Sipuleucel-T is a type of biologic therapy used to treat prostate cancer that has metastasized (spread to other parts of the body).
9. Bisphosphonate therapy:
Bisphosphonate drugs, such as clodronate or zoledronate, reduce bone disease when cancer has spread to the bone. Men who are treated with antiandrogen therapy or orchiectomy are at an increased risk of bone loss. In these men, bisphosphonate drugs lessen the risk of bone fracture (breaks). The use of bisphosphonate drugs to prevent or slow the growth of bone metastases is being studied in clinical trials.
What types of new treatments are being tested in clinical trials?
High-intensity focused ultrasound is a treatment that uses ultrasound (high-energy sound waves) to destroy cancer cells. To treat prostate cancer, an endorectal probe is used to make the sound waves.
Some patients may want to think about taking part in a clinical trial
For some patients, taking part in a clinical trial may be the best treatment choice. Clinical trials are part of the cancer research process. Clinical trials are done to find out if new cancer treatments are safe and effective or better than the standard treatment.
Many of today's standard treatments for cancer are based on earlier clinical trials. Patients who take part in a clinical trial may receive the standard treatment or be among the first to receive a new treatment.
Patients who take part in clinical trials also help improve the way cancer will be treated in the future. Even when clinical trials do not lead to effective new treatments, they often answer important questions and help move research forward.
Patients can enter clinical trials before, during, or after starting their cancer treatment.
Some clinical trials only include patients who have not yet received treatment. Other trials test treatments for patients whose cancer has not gotten better. There are also clinical trials that test new ways to stop cancer from recurring (coming back) or reduce the side effects of cancer treatment.
Follow-up tests may be needed.
Some of the tests that were done to diagnose the cancer or to find out the stage of the cancer may be repeated. Some tests will be repeated in order to see how well the treatment is working. Decisions about whether to continue, change, or stop treatment may be based on the results of these tests.
Some of the tests will continue to be done from time to time after treatment has ended. The results of these tests can show if your condition has changed or if the cancer has recurred (come back).
These tests are sometimes called follow-up tests or check-ups.
Treatment Options by Stage
Stage I : Prostate Cancer
Standard treatment of stage I prostate cancer may include the following:
Watchful waiting.
Active surveillance. If the cancer begins to grow, hormone therapy may be given.
Radical prostatectomy, usually with pelvic lymphadenectomy. Radiation therapy may be given after surgery.
External-beam radiation therapy. Hormone therapy may be given after radiation therapy.
Proton beam radiation therapy
Internal radiation therapy with radioactive seeds.
A clinical trial of high-intensity focused ultrasound.
Stage II: Prostate Cancer
Standard treatment of stage II prostate cancer may include the following:
Watchful waiting.
Active surveillance. If the cancer begins to grow, hormone therapy may be given.
Radical prostatectomy, usually with pelvic lymphadenectomy. Radiation therapy may be given after surgery.
External-beam radiation therapy. Hormone therapy may be given after radiation therapy.
Internal radiation therapy with radioactive seeds.
Proton beam radiation therapy
Cryosurgery.
A clinical trial of high-intensity focused ultrasound.
Clinical trials of new types of treatment, such as hormone therapy followed by radical prostatectomy.
Stage III: Prostate Cancer
Standard treatment of stage III prostate cancer may include the following:
External-beam radiation therapy. Hormone therapy may be given after radiation therapy.
Hormone therapy.
Radical prostatectomy. Radiation therapy may be given after surgery.
Watchful waiting.
Active surveillance. If the cancer begins to grow, hormone therapy may be given.
Treatment to control cancer that is in the prostate and lessen urinary symptoms may include the following:
External-beam radiation therapy.
Internal radiation therapy with radioactive seeds.
Hormone therapy.
Transurethral resection of the prostate (TURP).
A clinical trial of new types of radiation therapy.
Cryosurgery.
Stage IV: Prostate Cancer
Standard treatment of stage IV prostate cancer may include the following:
Hormone therapy.
Bisphosphonate therapy.
External-beam radiation therapy. Hormone therapy may be given after radiation therapy.
Alpha emitter radiation therapy.
Watchful waiting.
Active surveillance. If the cancer begins to grow, hormone therapy may be given.
A clinical trial of radical prostatectomy with orchiectomy.
A clinical trial of hormone therapy combined with chemotherapy.
Treatment to control cancer that is in the prostate and lessen urinary symptoms may include the following:
Transurethral resection of the prostate (TURP).
Radiation therapy.
Treatment Options for Recurrent Prostate Cancer
Standard treatment of recurrent prostate cancer may include the following:
Hormone therapy.
Chemotherapy for patients already treated with hormone therapy.
Biologic therapy with sipuleucel-T for patients already treated with hormone therapy.
External-beam radiation therapy.
Prostatectomy for patients already treated with radiation therapy.
Alpha emitter radiation therapy.
Prostate Cancer Prevention
What is prevention?
Cancer prevention is action taken to lower the chance of getting cancer. By preventing cancer, the number of new cases of cancer in a group or population is lowered. Hopefully, this will lower the number of deaths caused by cancer.
To prevent new cancers from starting, scientists look at risk factors and protective factors. Anything that increases your chance of developing cancer is called a cancer risk factor; anything that decreases your chance of developing cancer is called a cancer protective factor.
Some risk factors for cancer can be avoided, but many cannot. For example, both smoking and inheriting certain genes are risk factors for some types of cancer, but only smoking can be avoided. Regular exercise and a healthy diet may be protective factors for some types of cancer. Avoiding risk factors and increasing protective factors may lower your risk but it does not mean that you will not get cancer.
Different ways to prevent cancer are being studied, including:
Changing lifestyle or eating habits.
Avoiding things known to cause cancer.
Taking medicines to treat a precancerous condition or to keep cancer from starting.
How can I avoid risk factors? What can I do to increase protective factors to help prevent cancer?
Avoiding cancer risk factors may help prevent certain cancers. Risk factors include smoking, being overweight, and not getting enough exercise. Increasing protective factors such as quitting smoking, eating a healthy diet, and exercising may also help prevent some cancers. Talk to your doctor or other health care professional about how you might lower your risk of cancer.
What factors increase the risk of prostate cancer?
Age
Prostate cancer is rare in men younger than 50 years of age. The chance of developing prostate cancer increases as men get older.
Family history of prostate cancer
A man whose father, brother, or son has had prostate cancer has a higher-than-average risk of prostate cancer.
Race
Prostate cancer occurs more often in African-American men than in white men. African-American men with prostate cancer are more likely to die from the disease than white men with prostate cancer.
Hormones
The prostate needs male hormones to work the way it should. The main male sex hormone is testosterone. Testosterone helps the body develop and maintain male sex characteristics.
Testosterone is changed into dihydrotestosterone (DHT) by an enzyme in the body. DHT is important for normal prostate growth but can also cause the prostate to get bigger and may play a part in the development of prostate cancer.
Vitamin E
The Selenium and Vitamin E Cancer Prevention Trial (SELECT) found that vitamin E taken alone increased the risk of prostate cancer. The risk continued even after the men stopped taking vitamin E.
Folic acid
Folate is a kind of vitamin B that occurs naturally in some foods, such as green vegetables, beans and orange juice. Folic acid is a man-made form of folate that is found in vitamin supplements and fortified foods, such as whole-grain breads and cereals. A 10-year study showed that the risk of prostate cancer was increased in men who took 1 milligram (mg) supplements of folic acid. However, the risk of prostate cancer was lower in men who had enough folate in their diets.
Dairy and calcium
A diet high in dairy foods and calcium may cause a small increase in the risk of prostate cancer.
What protective factors that may decrease the risk of prostate cancer?
Folate
Folate is a kind of vitamin B that occurs naturally in some foods, such as green vegetables, beans and orange juice. Folic acid is a man-made form of folate that is found in vitamin supplements and fortified foods, such as whole-grain breads and cereals. A 10-year study showed that the risk of prostate cancer was lower in men who had enough folate in their diets. However, the risk of prostate cancer was increased in men who took 1 milligram (mg) supplements of folic acid.
Finasteride and Dutasteride
Finasteride and dutasteride are drugs used to lower the amount of male sex hormones made by the body. These drugs block the enzyme that changes testosterone into dihydrotestosterone (DHT). Higher than normal levels of DHT may play a part in developing prostate cancer. Taking finasteride or dutasteride has been shown to lower the risk for prostate cancer, but it is not known if these drugs lower the risk of death from prostate cancer.
The Prostate Cancer Prevention Trial (PCPT) studied whether the drug finasteride can prevent prostate cancer in healthy men 55 years of age and older. This prevention study showed there were fewer prostate cancers in the group of men that took finasteride compared with the group of men that did not. Also, the men who took finasteride who did have prostate cancer had more aggressive tumors. The number of deaths from prostate cancer was the same in both groups. Men who took finasteride reported more side effects compared with the group of men that did not, including erectile dysfunction, loss of desire for sex, and enlarged breasts.
The Reduction by Dutasteride of Prostate Cancer Events Trial (REDUCE) studied whether the drug dutasteride can prevent prostate cancer in men aged 50 to 75 years at higher risk for the disease. This prevention study showed there were fewer prostate cancers in the group of men who took dutasteride compared with the group of men that did not. The number of less aggressive prostate cancers was lower, but the number of more aggressive prostate cancers was not. Men who took dutasteride reported more side effects than men who did not, including erectile dysfunction, loss of desire for sex, less semen, and gynecomastia (enlarged breasts).
Selenium and vitamin E
These have not been proven not to affect the risk of prostate cancer, or their effects on prostate cancer risk are not known:
The Selenium and Vitamin E Cancer Prevention Trial (SELECT) studied whether taking vitamin E and selenium (a mineral) will prevent prostate cancer. The selenium and vitamin E were taken separately or together by healthy men 55 years of age and older (50 years of age and older for African-American men). The study showed that taking selenium alone or selenium and vitamin E together did not decrease the risk of prostate cancer.
Diet
It is not known if decreasing fat or increasing fruits and vegetables in the diet helps decrease the risk of prostate cancer or death from prostate cancer. In the PCPT trial, certain fatty acids increased the risk of high-grade prostate cancer while others decreased the risk of high-grade prostate cancer.
Multivitamins
Regular use of multivitamins has not been proven to increase the risk of early or localized prostate cancer. However, a large study showed an increased risk of advanced prostate cancer among men who took multivitamins more than seven times a week.
Lycopene
Some studies have shown that a diet high in lycopene may be linked to a decreased risk of prostate cancer, but other studies have not. It has not been proven that taking lycopene supplements decreases the risk of prostate cancer.
How are clinical trials for cancer prevention used to prevent cancer?
Cancer prevention clinical trials are used to study ways to prevent cancer.
Cancer prevention clinical trials are used to study ways to lower the risk of developing certain types of cancer. Some cancer prevention trials are conducted with healthy people who have not had cancer but who have an increased risk for cancer. Other prevention trials are conducted with people who have had cancer and are trying to prevent another cancer of the same type or to lower their chance of developing a new type of cancer. Other trials are done with healthy volunteers who are not known to have any risk factors for cancer.
The purpose of some cancer prevention clinical trials is to find out whether actions people take can prevent cancer. These may include eating fruits and vegetables, exercising, quitting smoking, or taking certain medicines, vitamins, minerals, or food suppleme
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