Prostate cancer
medical conditions

Prostate cancer

Explore the available health information, treatment context, and integrative evidence for Prostate cancer.

Background
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  • The prostate is part of a man's reproductive system, and is located in front of the rectum and under the bladder. It surrounds the urethra, the tube through which urine flows. A healthy prostate is about the size of a walnut. The prostate makes part of the seminal fluid. During ejaculation, seminal fluid helps carry sperm out of the man's body as part of semen. Male hormones (androgens) make the prostate grow. The testicles are the main source of male hormones, including testosterone. The adrenal gland, located above the kidneys, also makes testosterone, but in small amounts. If the prostate grows too large, it squeezes the urethra. This may slow or stop the flow of urine from the bladder to the penis.
  • Prostate tumors are masses of prostate cells. Prostate tumors can be benign (non-cancerous) or malignant (cancerous). Benign tumors in the prostate are rarely life-threatening. Benign prostatic hyperplasia (BPH) is the abnormal growth of benign prostate cells. The prostate grows larger and squeezes the urethra, preventing the normal flow of urine. BPH is a very common problem worldwide. Malignant or cancerous tumors of the prostate are generally more serious than benign tumors and may be life threatening. Malignant tumors can spread, or metastasize, to other parts of the body such as the lymph nodes, liver, bones, colon, and other organs.
  • When caught and treated early, prostate cancer has a cure rate of over 90%. It is extremely important to be diagnosed early, and healthcare professionals recommend men 50 years of age and older get screened for prostate cancer.
  • Prostate cancer is the most common non-skin cancer in America, affecting one in six men. More than 218,000 men in the United States will be diagnosed with prostate cancer in 2007.
  • Although only one in 10,000 men under the age of 40 will be diagnosed, the rate increases up to one in 39 for men between the ages of 40 to 59, and one in 14 for ages 60 to 69. More than 65% of all prostate cancers are diagnosed in men over the age of 65.
Risk Factors and Causes
  • Age: As men get older, (after age 50) their risk of prostate cancer increases. Individuals with risk factors for developing prostate cancer, or men above 50 years of age, should be checked for prostate cancer routinely.
  • Race or ethnicity: Prostate cancer exhibits tremendous differences in incidence among populations worldwide. Asian men typically have a very low incidence of prostate cancer, with age-adjusted incidence rates ranging from 2-10 per 100,000 men. Higher incidence rates are generally observed in northern European countries. African American men, however, have the highest incidence of prostate cancer in the world. In the United States, African American men have a 60% higher incidence rate compared with Caucasian men.
  • Family history: If an immediate family member such as a father or brother has prostate cancer, the risk of developing the disease is greater than that of the average American man. From 5-10% of prostate cancer cases are believed to be due primarily to high-risk inherited genetic factors or prostate cancer susceptibility genes.
  • Obesity: A high-fat diet and obesity may increase the risk of prostate cancer. Researchers theorize that fat increases production of the hormone testosterone, which may promote the development of prostate cancer cells. Obese men who are diagnosed with prostate cancer have more than two-and-a-half times the risk of dying from the disease as compared to men of normal weight at the time of diagnosis. Scientists believe that obesity increases the risk of prostate cancer by increasing inflammation and steroid hormones, such as testosterone.
  • High levels of testosterone: Because testosterone naturally stimulates the growth of the prostate gland, men who have high levels of testosterone, such as those with hypogonadism and men who use testosterone (steroid) therapy, are more likely to develop prostate cancer than are men who have lower levels of testosterone. Long-term testosterone treatment could cause prostate gland enlargement (benign prostatic hyperplasia or BPH). Also, doctors are concerned that testosterone therapy might fuel the growth of prostate cancer that is already present.
Signs and Symptoms
  • If the cancer is identified at its earliest stages, most men will not experience any symptoms. Some men, however, will experience symptoms that might indicate the presence of prostate cancer, including a need to urinate frequently, especially at night, difficulty starting urination or holding back urine, weak or interrupted flow of urine, painful or burning urination, difficulty in having an erection, painful ejaculation, blood in urine or semen, or frequent pain or stiffness in the lower back, hips, or upper thighs. Because these symptoms can also indicate the presence of other conditions, such as urinary tract infections or bladder problems, men who experience any of these symptoms will undergo a thorough work-up to determine the underlying cause of the symptoms.
Diagnosis
  • Exams and tests :
  • Digital rectal exam (DRE): The digital rectal exam is a procedure commonly performed during routine physical examinations. During a DRE, a doctor feels the prostategland by passing a gloved finger into the patient's rectum tofind hard or lumpy areas of the gland, which may represent anabnormality.
  • Prostate-specific antigen (PSA) test: Prostate specific antigen (PSA) is an enzyme that participates in breaking down proteins in seminal fluid and plays an important role in fertility. A blood sample is drawn from a vein and analyzed for PSA, a protein that is naturally produced by the prostate gland. The highest amounts of PSA are found in the seminal fluid. It is normal for the blood stream to contain a small amount of PSA. However, if a higher than normal level is found, it may be an indication of prostate infection, inflammation, enlargement or cancer. Normal levels of PSA are less than 4.0 nanograms per milliliter (ng/ml), meaning that anything above 4.0 ng/ml is abnormal. If the PSA is elevated, or if the individual has an abnormal digital rectal exam, then further tests may be needed.If the PSA is elevated, further tests may be needed to investigate the cause of the discrepancy. However, these findings do not necessarily mean that a patient has prostate cancer. A DRE will also be performed.
  • Using the PSA test to screen men for prostate cancer is controversial because it is not yet known if this test actually saves lives. Moreover, it is not clear if the benefits of PSA screening outweigh the risks of follow-up diagnostic tests and cancer treatments. For example, the PSA test may detect small cancers that would never become life threatening. This situation, called overdiagnosis, puts men at risk for complications from unnecessary treatment such as surgery or radiation.
  • Prostate biopsy: If DRE and PSA test results suggest prostate cancer, a doctor may recommend a prostate biopsy. The patient will be prescribed antibiotics, usually a three day course, before the surgery. Most individuals receive local anesthesia, such as lidocaine (Xylocaine®). To do a biopsy, a doctor inserts a small, lubricated probe about the size and shape of a cigar into the rectum (called transrectal ultrasound). The probe uses sound waves that are converted to visual data in order to see a picture of the prostate gland, which is then analyzed for changes. If an abnormal area is seen on the transrectal ultrasound, the doctor will likely biopsy that area. Then a fine, hollow needle is aimed at these areas of the prostate. A spring propels the needle into the prostate gland and retrieves a very thin section of tissue. Biopsies in general take 15-45 minutes to complete, depending upon the procedure. The procedure used to diagnose prostate cancer (prostate biopsy) may cause side effects, including bleeding and infection. Fifty-five percent of men report discomfort during the biopsy. The same procedure can be performed through the perineum area (between the anus and the scrotum, called transperineal biopsy), or through the urethra (canal that the urine travels through for elimination, called transurethral biopsy).
  • If a doctor thinks the cancer may have spread to other parts of the body, other tests may be used. These include procedures such as a bone scan, ultrasound, computerized tomography (CT) scan, magnetic resonance imaging (MRI), and lymph node biopsies.
  • Grading :
  • Once the presence of cancer is confirmed by a biopsy, the doctor determines how aggressive the cancer is and assigns it a corresponding grade. This is done by examining and comparing tissue samples of cancerous cells and healthy prostate cells. Cancer cells may vary in shape and size. Some cells may be aggressive, while others are not. More aggressive cancers generally receive more aggressive treatments. Prognosis is also poorer if the cancer is aggressive.
  • The Gleason score is a tumor grading procedure used to judge how aggressive a tumor might be. During the Gleason scoring process, the pathologist takes the numbers for the two most representative types of cells seen in the prostate biopsy and adds them together. Two representative cell types seen in the tumor are rated with a number from 1=normal to 5=very abnormal. Then each of the numbers are added together to give a Gleason score.
  • Gleason scores will range from two to ten, with two being completely normal, and ten very aggressive cancer. Generally Gleason scores of seven or above indicate a more serious prognosis with the chance that the tumors will be quite aggressive and spread quickly unless brought under control.
  • Staging :
  • Two systems are commonly used for the staging of prostate cancer: the Jewett system (stages A through D) and the American Joint Committee on Cancer (AJCC) tumor, nodes, and metastasis (TNM) system. Both systems take into account the size of the tumor, whether the lymph glands (also called lymph nodes) are affected, and whether the tumor has metastasized (spread to other areas of the body). In general, prostate cancer has four basic stages:
  • Stage A: In stage A, the cancer is very small and completely inside the prostate gland which feels normal when a rectal examination is performed.
  • Stage B: Stage B cancer is still inside the prostate gland, but is larger and a lump or hard area can be felt when a rectal examination is done.
  • Stage C: Stage C cancer has broken through the covering of the prostate and may have grown into the seminal vesicles.
  • Stage D: Stage D cancer has grown into the neck of the bladder, rectum or pelvic wall, or has spread to the lymph nodes or another part of the body.
Complications
  • Prostate cancer can metastasize (spread to nearby areas in the body) and can be life-threatening. Metastasis can take months to years, depending on the individual. Although early-stage prostate cancer typically is not painful, once it has spread to bones, it may produce pain, which can be intense. Urinary incontinence (leakage) may occur, erectile dysfunction (impotence), or depression may also occur.
Treatment
  • Prostate cancer is generally slow growing and occurs in older men (over the age of 65). If the individual is not experiencing symptoms, healthcare professionals can use watchful waiting. Watchful waiting is the close monitoring an individual's condition without giving any treatment until symptoms appear or change. When a patient does need treatment, there are several conventional options available, which include surgeries, radiation, or hormone therapies. Patients with prostate cancer have a choice about their treatment.
  • Surgery :
  • Radical prostatectomy: Radical prostatectomy is a surgical procedure to remove the prostate, surrounding tissue, and seminal vesicles. There are two types of radical prostatectomy, including retropubic prostatectomy, during which the prostate and nearby lymph nodes are removed through an incision (cut) in the abdominal wall, and perineal prostatectomy, a surgical procedure to remove the prostate and nearby lymph nodes through an incision made in the perineum (area between the scrotum and anus).
  • Transurethral resection of the prostate (TURP): This is a surgical procedure to remove tissue from the prostate that may be blocking urine flow using a resectoscope (a thin, lighted tube with a cutting tool) inserted through the urethra. This surgery is sometimes performed to relieve symptoms caused by benign (non-cancerous) tumors. Transurethral resection of the prostate may also be done in men who cannot have a radical prostatectomy because of age or illness.
  • Surgery complications: Surgery for prostate cancer can cause problems such as impotence (erectile dysfunction) and leakage of urine from the bladder or stool from the rectum. In some cases, doctors can use a technique known as nerve-sparing surgery. This type of surgery may save the nerves that control erection. These surgeries are performed under general anesthesia, which may also cause complications.
  • Radiation therapy :
  • Radiation therapy is a cancer treatment that uses high-energy radiation to kill cancer cells and shrink tumors. Radiation targets rapidly growing cancer cells and helps decrease metastasis, or the spreading to other areas of the body. There are two types of radiation therapy. External radiation therapy (XRT) uses a machine outside the body to send radiation toward the cancer. Internal radiation therapy (or brachytherapy) involves surgically implanting tiny, radioactive capsules (called "seeds") into the cancerous prostate gland. The seeds emit radiation that kills the malignant tumor. The type of radiation therapy used depends on the type and stage of the cancer being treated. Side effects can include diarrhea, skin burns, sexual dysfunction, and urinary discomfort or urgency. Normal tissue can be damaged by radiation. However, new developments in radiation delivery may decrease the chances of damage.
  • Hormone therapy :
  • Hormone therapy is utilized in cancer treatment to remove hormones or block their action, ultimately inhibiting the growth of cancer cells. Hormones are substances produced by glands in the body that circulate within the bloodstream and exert specific effects on the body. Some hormones can contribute to the growth of certain cancers. If laboratory tests show that the cancer cells have receptors (places of attachment) for hormones, then drugs, surgery, or radiation therapy are used to reduce the production of hormones or block them from working. Side effects may include nausea, vomiting, hot flashes, impaired sexual function, loss of desire for sex, and breast tenderness may occur in men treated with hormone therapies. Patients who begin hormone therapy may experience an increase in prostate cancer symptoms for approximately two weeks, due to a temporary increase in testosterone levels.
  • Luteinizing hormone-releasing hormone agonists: These drugs can prevent the testicles from producing testosterone (the male hormone). Examples are leuprolide (Eligard®, Lupron®, Lupron Depot®, Viadur®), goserelin (Zoladex®), and buserelin (Suprefact®).
  • Antiandrogens: Antiandrogens can block the action of androgens (hormones that promote male sex characteristics). Two examples are flutamide (Eulexin®) and nilutamide (Anandron®). Healthcare professionals recommend that patients who are taking antiandrogens get periodic liver function tests and should report symptoms such as nausea and vomiting, stomach pain, fatigue (extreme tiredness), appetite loss, dark urine, and yellowing of the eyes to their physician immediately.
  • Adrenal agents: Drugs that can prevent the adrenal glands from making androgens (male sex hormones) include aminoglutethimide (Cytadren®). Side effects include drowsiness, dizziness, headache, weakness, nausea, or loss of appetite during the first few weeks of treatment. As the body adjusts to the medication, the symptoms should disappear. If symptoms persist after two weeks, healthcare professionals recommend contacting a doctor.
  • Estrogens: Estrogens (hormones that promote female sex characteristics) can prevent the testicles from producing testosterone or the male hormone. However, estrogens are seldom used today in the treatment of prostate cancer because of the risk of serious side effects, including breast cancer development and an increase in stroke (neurological damage caused by lack of oxygen to the brain), or heart attack. Estrogens include conjugated estrogen (Premarin®) or estradiol (Ogen®).
  • Other therapies :
  • Cryosurgery: Cryosurgery is a treatment that uses an instrument to freeze and destroy prostate cancer cells. This type of treatment is also called cryotherapy. Cryotherapy alone rarely causes side effects. However, when used after the individual has undergone radiation therapy for the prostate cancer, it increases the risks of side effects. The rates of incontinence, or the involuntary excretion of urine from the body, in patients undergoing cryosurgery after radiation (either seeds or external beam) are 60-70%, compared to less than 1% of patients undergoing cryosurgery who have not had any prior radiation. Other risks of side effects, such as sexual dysfunction and pain, are increased when using cryosurgery after treatment with radiation. The severity of the side effects in the previously radiated group is directly related to the extent of freezing and the total amount of ice that is generated during the procedure.
  • 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. Chemotherapy is often used to treat prostate cancers that are resistant to hormonal treatments. An oncology (cancer) specialist will usually recommend a single drug or a combination of drugs. Chemotherapy medications that may be used to treat prostate cancer include mitoxantrone (Novantrone®), paclitaxel (Taxol®), docetaxel (Taxotere®), estramustine (Emcyt®), and doxorubicin (Adriamycin®). Common side effects of chemotherapy depend on the type of drug used, dosage, and length of treatment. The most common side effects are fatigue, nausea and vomiting, diarrhea, hair loss, and increased susceptibility to infection.
  • 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. This type of cancer treatment is also called biotherapy or immunotherapy. Side effects include fever, chills, nausea, and vomiting.
  • High-intensity focused ultrasound: High-intensity focused ultrasound is a treatment that uses ultrasound (high-energy sound waves) to destroy cancer cells. To treat prostate cancer, an endorectal (inside the rectum) probe is used to make the sound waves.
  • When the individual has not responded to treatment methods, the cancer has metastasized (spread to other areas of the body), and the prognosis is not good, palliative care (provides symptomatic relief but not a cure) may be chosen over aggressive therapies and the side effects associated with them.
Prevention
  • Prostate screening: The American Urological Association (AUA) encourages men who are in good health to have annual PSA testing starting at age 50, or at age 40 if they're in high-risk groups, such as black men or those with a father, brother, or son with the disease.
  • Vaccine: A new vaccine, although not FDA-approved, has been developed to help extend survival for patients with deadly metastatic prostate cancer. The FDA has requested additional clinical data before the vaccine, called Provenge®, can be approved. The vaccine is targeted at individuals with prostate cancer who have ceased responding to hormone therapy and have cancer that has spread to other organs and tissues. Reported side effects include fever, chills, and fatigue (tiredness).
  • Lifestyle changes: Diets should include less high-fat dairy products, such as cheese, sour cream, and ice cream. High fat dairy products and the calcium contained in dairy may increase the risks of developing prostate cancer. Cruciferous vegetables (such as broccoli, cabbage, and cauliflower) have been reported to contain cancer-fighting phytochemicals that may decrease the chances of developing prostate cancer. Antioxidant containing foods, including fruits (such as berries, grapes, and tomatoes) and vegetables (such as peppers and carrots) may help prevent the development of prostate cancer. Dietary consumption of red meat and/or processed meats may increase the risks of developing cancer of the colon, rectum, stomach, pancreas, bladder, ovaries, prostate, breast and lung, and other diseases such as heart disease, rheumatoid arthritis, type 2 diabetes, and Alzheimer's disease. Exercise (at least 30 minutes daily for five days a week), smoking cessation, and relaxation all may contribute to decreasing the risk factors associated with developing prostate cancer.
References

Natural Standard developed the above evidence-based information based on a thorough systematic review of the available scientific articles. For comprehensive information about alternative and complementary therapies on the professional level, go to www.naturalstandard.com. Selected references are listed below.

  • American Academy of Family Physicians. . Accessed April 22, 2009.
  • American Cancer Society. . Accessed April 22, 2009.
  • American Urological Association. . Accessed April 22, 2009.
  • Koh KA, Sesso HD, Paffenbarger RS Jr, Lee IM. Dairy products, calcium and prostate cancer risk. Br J Cancer. 2006;95(11):1582-5. . View Abstract
  • Kristal AR, Stanford JL. Cruciferous vegetables and prostate cancer risk: confounding by PSA screening. Cancer Epidemiol Biomarkers Prev. 2004;13(7):1265. . View Abstract
  • Natural Standard: The Authority on Integrative Medicine. . Copyright © 2009. Accessed April 22, 2009
  • Peters U, Foster CB, Chatterjee N, et al., Serum selenium and risk of prostate cancer-a nested case-control study. Am J Clin Nutr. 2007 Jan;85(1):209-17. . View Abstract
  • Prostate Cancer Foundation.com . Accessed April 22, 2009.