Prostate cancer is a disease in which cancer cells grow in the prostate gland. The prostate is a walnut-sized gland in men that surrounds the urethra. The prostate produces a fluid that is part of semen.
Cancer occurs when cells in the body (in this case prostate cells) divide without control or order. Normally, cells divide in a regulated manner. If cells keep dividing uncontrollably when new cells are not needed, a mass of tissue forms, called a growth or tumor. The term cancer refers to malignant tumors, which can invade nearby tissue and spread to other parts of the body. A benign tumor does not invade or spread.
The sooner prostate cancer is treated, the more favorable the outcome. If you suspect your might have this condition, contact your doctor immediately.
Causes
The cause of prostate cancer is unknown. However, research shows that certain risk factors are associated with the disease.
Risk Factors
A risk factor is something that increases your chance of getting a disease or condition.
The following factors increase your chance of developing prostate cancer:
-
Age: 55 or older
-
Race: Black
-
Family history of prostate cancer, especially father or brother
-
Family history of prostate cancer diagnosed at a young age
-
A high-fat diet
Symptoms
-
A need to urinate frequently, especially at night
-
Difficulty starting urination or holding back urine
-
Inability to urinate
-
Weak or interrupted flow of urine
-
Painful or burning urination
-
Difficulty having an erection
-
Painful ejaculation
-
Blood in urine or semen
-
Frequent pain or stiffness in the lower back, hips, or upper thighs
These symptoms may also be caused by other, less serious health conditions, such as benign prostatic hyperplasia (BPH) or an infection. A man experiencing these symptoms should see a doctor.
Diagnosis
Your doctor will ask about symptoms and medical history, and perform a physical exam. Tests may include:
-
Digital Rectal Exam–examination of the rectum with the doctor's gloved finger inserted into your rectum
-
Urine Test–to check for blood or infection
-
Blood Test–to measure prostate specific antigen (PSA) and prostatic acid phosphatase (PAP)
Other tests to learn more about the cause of your symptoms may include:
Transrectal Ultrasonography–a test that uses sound waves and a probe inserted into the rectum to find tumors
Intravenous Pyelogram–series of x-rays of the organs of the urinary tract
Cystoscopy–a procedure in which a doctor looks into the urethra and bladder through a thin, lighted tube
Biopsy–removal of a sample of prostate tissue to test for cancer cells
Treatment
Once prostate cancer is found, tests are performed to find out if the cancer has spread and, if so, to what extent. Treatment depends on the extent of the cancer. To understand your treatment options, you may want to consult with a urologist and a radiation oncologist for help deciding what is the best treatment plan for you. It is important to discuss your individual benefits and risks associated with each treatment option with your doctors. For some treatments, the expense and risks associated with the treatment may not outweigh the benefits.
Standard treatment options include:
Watchful Waiting
Watchful waiting involves no treatment, but your doctor tests periodically to see if the cancer is growing. Watchful waiting is suggested for::
Surgery
Surgery for prostate cancer involves the removal of the cancerous tumor and nearby tissues, and possibly nearby lymph nodes. Surgery is generally offered to patients who are in good health and are younger than 70 years old. Types of surgery include:
-
Pelvic Lymphadenectomy–removal of lymph nodes in the pelvis to determine if they contain cancer; if they do, removal of the prostate and other treatment may be recommended
-
Radical Retropubic Prostatectomy–removal of the entire prostate and nearby lymph nodes through an incision in the abdomen
-
Radical Perineal Prostatectomy–removal of the entire prostate through an incision between the scrotum and the anus; nearby lymph nodes are sometimes removed through a separate incision in the abdomen
-
Transurethral Resection of the Prostate (TURP)–removal of part of the prostate with an instrument inserted through the urethra; a TURP is not a cancer surgery, but can be used to relieve the symptoms of obstruction when a patient has either prostate cancer or an enlarged gland due to other reasons
Prostate cancer surgery can result in impotence and leakage of urine from the bladder or stool from the rectum. Nerve-sparing surgery may reduce these risks, but very large tumors or tumors that are very close to nerves may not be treatable with nerve-sparing surgery.
In addition to traditional surgery, robotic surgery and laparascopic surgery may be options in your community. These minimally invasive techniques can help reduce side effects, blood loss, and recovery time over traditional “open” surgery.
Radiation Therapy
Radiation therapy involves the use of radiation to kill cancer cells and shrink tumors. Radiation may be:
-
External Radiation Therapy–radiation directed at the tumor from a source outside the body
-
Internal Radiation Therapy–dozens of tiny radioactive seeds are implanted directly into the prostate gland using needles; the seeds remain in the prostate gland permanently and harmlessly; this method delivers radiation directly to the affected area, and reduces the risk of damage to surrounding areas such as the rectum and bladder; internal radiation therapy is most often used for treating earlier stage cancers
Radiation therapy for prostate cancer may result in impotence and urinary problems. However, most studies show that rates of impotence are less for radiation therapy than for standard prostatectomy and slightly less than that for nerve-sparing procedures. Incontinence following radiation therapy is also less than following prostatectomy, but there is a slightly increased risk of cystitis due to radiation.
Hormone Therapy
Hormone therapy is often used for patients whose prostate cancer has spread beyond the prostate or has recurred after treatment. The goal of hormone therapy is to lower levels of the male hormones, also known as androgens. The main androgen is testosterone. Lowering androgen levels can cause prostate cancers to shrink or grow more slowly, but does not cure cancer. Methods of hormone therapy include:
-
Orchiectomy–a surgical procedure to remove one or both of the testicles, which are the main source of male hormones; orchiectomy decreases hormone production, which can shrink or slow the growth of most prostate cancers
-
Luteinizing Hormone-releasing Hormone (LHRH) Agonists–injections that can decrease the amount of testosterone produced by the testicles
-
Antiandrogens (eg, flutamide, bicalutamide)–medications that can block the action of androgens; these medications are often used in combination with orchiectomy or LHRH agonists, a combination called total androgen blockade
-
Drugs That Prevent Adrenal Glands From Producing Androgens (eg, ketoconazole, aminoglutethimide)
-
Estrogens–drugs that can prevent the production of testosterone in the testicles; estrogens are rarely used today because of the risk of serious side effects
Hormone therapy for prostate cancer may result in hot flashes, impaired sexual function, loss of sexual desire, and weakened bones.
Other Treatment Options
In addition to standard treatments, other treatments are being investigated in clinical trials. Patients may want to consider taking part in a clinical trial when weighing treatment options. The treatments that are currently being tested include:
Cryosurgery
Cryosurgery uses an instrument to freeze and destroy prostate cancer cells.
Chemotherapy
Chemotherapy is the use of drugs to kill cancer cells. It may be given in many forms, including: pill, injection, and via a catheter. The drugs enter the bloodstream and travel through the body, killing mostly cancer cells, but also some healthy cells. Since chemotherapy in the treatment of prostate cancer is still being investigated, it is not clear whether it can prolong survival in men with prostate cancer.
Biological Therapy
Biological therapy is the use of medications or substances made by the body to increase or restore the body’s natural defenses against cancer. It is also called biological response modifier (BRM) therapy.
High-intensity Focused Ultrasound
This treatment uses an endorectal probe that produces ultrasound (high-energy sound waves), which can destroy cancer cells.
Conformal Radiation Therapy
Conformal radiation therapy uses three-dimensional radiation beams that are conformed into the shape of the diseased prostate. This treatment spares nearby tissue the damaging effects of radiation.
Intensity-Modulated Radiation Therapy (IMRT)
IMRT uses radiation beams of different intensities to deliver higher doses of radiation therapy to the tumor and lower doses to nearby tissues at the same time.
Prevention
Beginning at age 50, men should be offered a digital rectal exam and PSA blood test to screen for prostate cancer. Many, but not all professional organizations, recommend a yearly PSA blood test for men over age 50 to screen for prostate cancer. Black men and men with close family members who have had prostate cancer diagnosed at a young age should begin screening at age 45. All men should discuss PSA testing with their physician.
RESOURCES:
American Cancer Society
http://www.cancer.org
American Urological Association
http://www.afud.org
National Cancer Institute
http://www.cancer.gov
National Prostate Cancer Coalition
http://www.pcacoalition.org
References:
American Cancer Society website. Available at: http://www.cancer.org.
Know your options: a prostate cancer education program. National Cancer Institute website. Available at: http://www.cancer.gov/PDF/d00d7731-d7a9-4219-aff1-16d62b8cbe96/knowyouroptions.pdf. Accessed November 10, 2005.
National Cancer Institute website. Available at: http://www.cancer.gov/.
Prostate cancer (PDQ): treatment. National Cancer Institute website. Available at: http://www.cancer.gov/cancertopics/pdq/treatment/prostate/patient. Accessed November 10, 2005.
Radiation therapy for cancer: questions and answers. National Cancer Institute website. Available at: http://www.cancer.gov/cancertopics/factsheet/Therapy/radiation. Accessed November 10, 2005.
