Prostate cancer is a tumor that grows in the prostate gland in men. The prostate gland is part of the reproductive system. It stores seminal fluid, the substance that mixes with sperm to form semen.
Normally, the prostate is a firm, walnut-shaped gland at the base of a man's bladder. It surrounds the urethra, the tube that carries urine from the bladder to the outside of the body. A man with prostate cancer has a tumor in the prostate gland. In some cases, prostate cancer can grow slowly for many years. Other times, it may grow rapidly and spread swiftly to other parts of the body. It may also spread its cells throughout the lymph system or bloodstream and along nerve pathways.
No one knows what causes prostate cancer. Hormones, such as testosterone, control the growth of the prostate gland. They may contribute to prostate cancer. Viruses or chronic infections may contribute to prostate cancer. Researchers have recently identified a gene that is linked to some cases of prostate cancer. So far, prostate cancer has not been linked to common cancer-causing substances in the environment.
Following are some of the risk factors.
Men who have had a vasectomy, who smoke, or who have been exposed to a metal called cadmium may also be at an increased risk.
Some men with prostate cancer have no symptoms. Others notice symptoms such as the following:
If the cancer has spread to other parts of the body, the man may have painful bony sites. He may also have occasional nerve paralysis or loss of bladder function.
Diagnosis of prostate cancer begins with a medical history and physical exam. The healthcare provider will do a digital rectal exam. This involves inserting a gloved finger into the man's rectum to feel the prostate.
The PSA test, and a more refined version of it, may help in diagnosing prostate cancer. High levels of PSA suggest, but cannot prove, that a man has prostate cancer. However, very high levels of PSA can diagnose the disease. Normal ranges for PSA increase with age and are different according to race.
If prostate cancer is suspected, a biopsy may be done. During the biopsy, a needle is inserted into the prostate gland to obtain a small sample of tissue. The healthcare provider may order a transrectal ultrasound. This test uses sound waves to examine the inside of the gland. It can be used to guide the healthcare provider during a biopsy. If several areas of the prostate are in question, a number of biopsies may be done. The tissue is sent to a lab where it will be checked for cancer.
Prostate cancer is graded and staged for aggressiveness based on how far it has spread throughout the body.
CT scans and bone scans help in staging. Sometimes staging only becomes clear at the time of surgery.
As yet, prostate cancer cannot be completely prevented. Prostate screening with exams and blood tests helps with early diagnosis. The American Cancer Society, also called ACS, recommends that a digital rectal exam be offered every year to men 50 years of age or older who have a life expectancy of at least 10 years. A digital rectal exam involves a healthcare provider inserting his or her finger into a man's rectum to check if the patient's prostate is enlarged.
The ACS also recommends that a prostate-specific antigen test, also called a PSA blood test, be offered every year to men 50 years of age or older who have a life expectancy of at least 10 years. ACS recommends that screening start at the age of 45 years for African American men or men with a family history of prostate cancer.
Good dietary choices may also help prevent prostate cancer. The diet should be low in fat. Fruits, vegetables, and fatty fish help lower a man's risk for prostate cancer.
Long-term effects of prostate cancer depend on its stage and the type of treatment used. Some men who have slow-growing cancer can be monitored without treatment. Others live for a long time with prostate cancer that has spread to other sites in the body. Cancer that has spread is not curable in most cases. Unless other illnesses occur first, cancer that has spread usually causes death.
Prostate cancer is not contagious and poses no risk to others. Prostate cancer does run in families. Brothers or sons of men who develop cancer should be aware of their family history. They should be screened for the disease as they grow older, as recommended by the ACS.
The proper management of the many stages of prostate cancer is controversial. Depending on the grade and stage of the cancer, some options are as follows:
Hormone therapy or chemotherapy is used mostly for men with advanced stage D disease. Hormone therapy includes use of the following:
Treatment for men with prostate cancer that has spread through the body is usually confined to making them as comfortable as possible. Often the prostate is not removed. A cure for prostate cancer is not available. Researchers continue to search for a cure.
Following are some common side effects of radiation or surgery for prostate cancer:
Occasionally, radiation or surgery may cause the following:
Depending on exact treatment, hormone therapy may cause the following conditions:
Often given intravenously, chemotherapy has certain common side effects, such as:
Cryosurgery or radiation implants can be painful and expensive. However, these treatments may preserve sexual function.
After treatment, men are regularly monitored for side effects and a recurrence of the cancer.
The following are used to monitor the disease:
Any new or worsening symptoms should be reported to the healthcare provider.
Author:Thomas Fisher, MD
Editor:Ballenberg, Sally, BS
Reviewer:Melissa Sanders, PharmD