Cancer of the prostate, a common form of cancer, is a disease in which cancer (malignant) cells are found in the prostate. The prostate is on the male sex glands, and is located just below the bladder and in front of the rectum. The size of the prostate is about the size of a walnut. It surrounds the part of the urethra, the tube that carries urine from the bladder to the outside of the body. The prostate makes fluid that becomes part of the semen, which contains sperm. Prostate cancer is most commonly found in older men.
As a man gets older, his prostate may get bigger and block the urethra of bladder, which can cause him to have difficulty urinating or even interfere with sexual functions. This condition is called benign prostatic hyperplasia (BPH), and although it is not cancer, surgery may be needed to correct it. The symptoms of BPH, or other problems in the prostate may be similar to symptoms of prostate cancer. Some common symptoms of prostate cancer are: weak or interrupted flow of urine, urinating often (especially at night), difficulty urinating, pain or burning from urinating, blood in the urine, and nagging pain in the back, hips, or pelvis. Often, there are no early symptoms of prostate cancer.
Once cancer of the prostate has been found, tests are done to find out if cancer cells have spread from the prostate to tissues around it, or to other parts of the body. This is called “staging.” It is very important to know the stage if the disease to plan for the treatment. The following stages are used for prostate cancer:
Prostate cancer at this stage cannot be felt and causes no symptoms. The cancer is only in the prostate and usually is found accidentally when surgery is done for other reasons, such as BPH. Cancer cells may be found in one, or many areas of the prostate.
The tumor may be shown by a blood test or felt in the areas of the prostate during rectal exam, but the cancer cells are only in the prostate gland.
Cancer cells have spread outside the covering (capsule) of the prostate to tissues surrounding it. The seminal vesicles may also have cancer in them.
Cancer cells have spread to lymph nodes near or far from the prostate, or to other organs and tissues, such as the liver or lungs.
Prostate staging can also be described using T (tumor size), N (extent of spread to lymph nodes), and M (extent of spread to other parts of the body).
Three kinds of treatments for prostate cancer that are commonly used are Surgery (taking out the cancer), radiation therapy (using high dose x-rays or other high energy rays to kill cancer cells), and hormone therapy (using hormones to stop cancer cells from growing). Surgery is the most common of the three treatments.
The cancer may be removed by either radical prostatectomy, transurethral resection, or cryosurgery (removing the cancer by freezing it. Radical prostatectomy removes the prostate and some the tissues that surround it. This surgery may be done by cutting into the space between the scrotum and the anus in an operation called a perneal prostatectomy, or by cutting into the lower abdomen in an operation called a retropubic prostatectomy. Radical prostatectomy is done only if the cancer has not spread outside the prostate. Often, a surgery to remove the lymph nodes in the pelvis, called pelvic lymph node dissection, is done to make sure the cancer has not spread outside the prostate. If it is found out that the lymph nodes do have cancer, a prostatectomy will most likely not be performed.
Transurethral resection cuts the cancer from the prostate using a tool with a small wire loop on the end that is put into the prostate through the urethra. This operation is sometimes done to relieve symptoms caused by the tumor before other treatment, or in men who cannot have a radical prostatectomy because of age or other illnesses.
Radiation therapy uses high x-rays to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body, or from putting materials that produce radiation through thin plastic tubes in the area where the cancer is found. A side effect from radiation therapy is impotence.
Hormone therapy for prostate cancer can take many forms. Male hormones can actually help prostate cancer grow. To stop the cancer from growing, drugs that decrease the amount of male hormones made may be given. Sometimes, an operation to remove the testicles is done to stop the testicles from making testosterone. Hot flashes are a side effect of hormone therapy.
Current research of prostate cancer has linked it to the X chromosome, which is one of two chromosomes that determine sex in mammals. This is the first time that a gene for a common type of cancer has been linked to the X chromosome. Dr. Patrick C. Walsh of John Hopkins said, “This is a major step toward a better understanding of the factors responsible for prostate cancer, and would not have possible without the intense effort and collaboration of a large number of scientists and patients in the U.S., Finland, and Sweden.” Dr. Francis Collins said, “Mapping HPCX brings us one step closer to understanding the origins of prostate cancer…Now we need to identify the precise gene and the misspelling which correlated with risk of cancer.” Knowing where prostate cancer comes from will enable doctors to determine who is more at risk then others so that they will be able to prevent future patients from getting it.
Surgical castration is the most cost-effective treatment for prostate cancer, but it is not the choice of many. A new method is to target a beam of high-intensity ultrasound at the prostate. This may destroy cancer cells, and have few side effects. However, there have only been preliminary studies, so evidence is not conclusive. Another method being tested is implanting radioactive seeds into the prostate. This method is called brachytherapy, in which pellets smaller then grains of rice are inserted into the prostate. Preliminary studies show much success, and it is believed that this method can be better then surgery.
There are many treatments today for prostate cancer, and many more potential cures. However, today, there is nothing that can be done to permanently remove the cancer. All that can be done now is slow down the process. Hopefully, in the future with all the medical advances, someone will be able to find a cure to help the thousands of men that suffer and die each year from this terrible disease.
The Prostate Book, Rous.
The Prostate Book, Rous.
Anatomy and Physiology