What Is Prostate Cancer?
Prostate cancer is the development of cancer cells in the prostate gland (a gland that produces fluid for semen). It is a very common cancer in men; some cancers grow very slowly while others are very aggressive and spread quickly to other organs.
Prostate Cancer Symptoms
Symptoms of prostate cancer are variable; some men have no symptoms until the cancer develops over years. However, symptoms that can develop include the following:
- Urinary frequency
- Difficulty starting or stopping urination
- Interrupted or weak or slow urinary stream
- Blood in urine or in semen
- Discomfort (pain or burning sensation with urination or ejaculation)
- Intense pain in the low back, hips, or thighs, often present with aggressive or prostatic cancer spread to other organs
Prostate Cancer or Enlarged Prostate?
Two conditions can cause some symptoms that mimic those seen in prostate cancer described previously. The first is termed benign prostatic hyperplasia (BPH). BPH results from the prostate growing larger but the growth is not cancerous. BPH causes symptoms by creating pressure on the bladder, urethra, or both. BPH commonly occurs in elderly men. The second condition is termed prostatitis (inflammation or infection of the prostate gland). Both conditions are treated medically but some individuals with BPH may require surgical treatment.
Uncontrollable Risk Factors
Aging in men (beginning at age 50) is the greatest risk factor for both BPH and prostate cancer. In addition, having a father or brother with prostate cancer doubles the risk for prostate cancer; however, African American males have the highest risk for prostate cancer. Research suggests that the majority of men at age 70 have some form of prostatic cancer with most of them showing no symptoms.
Controllable Risk Factors
Researchers suggest a diet low in fruits and vegetables but high in meats and high-fat dairy products increases the risk for prostate cancer. The mechanism(s) for this is being investigated but current speculation suggests meat and high-fat foods contain compounds that augment the growth of cancer cells.
Prostate Cancer Myths
There are many myths about why prostate cancer develops. However, there is no evidence that "too much sex," masturbation, benign prostatic hyperplasia (BPH), or a vasectomy increases the risk or causes prostate cancer. Current research is investigating if STDs, prostatitis, or alcohol use increase the risk of developing prostate cancer.
Can Prostate Cancer Be Found Early?
Although screening tests are not routinely done for prostatic cancers, the American Cancer Society guidelines suggest the following men discuss getting screening tests:
- Men aged 40 with more than one close relative (father, brother, or son) diagnosed with prostate cancer at an early age
- Men aged 45 that are African American or have a father, brother, or son diagnosed with prostate cancer before age 65
- Men aged 50 or older who have average risk and expect to live at least 10 more years
However, not everyone agrees with these guidelines; clinicians should explain that treatments can have severe side effects and that some cancers are so slow-growing that treatments may have little or no effects on the cancer.
DRE and PSA Screening
A digital rectal exam (DRE) is done to determine if the prostate is enlarged and is either soft or has bumps or is very firm (hard prostate). Another test done on a blood sample can determine the level of a protein (prostate-specific antigen or PSA) produced by prostate cells. The PSA test may indicate a person has a higher chance of having prostate cancer but controversies about the test exist (see following slide). The patient and his doctor need to carefully consider the meaning and the use of these test results.
PSA Test Results
As stated above, the PSA test has some problems associated with it. In general, a PSA level less than 4 nanograms per mililiter (ng/mL) of blood is considered a normal level while a PSA greater than 10 ng/mL suggests a high risk of having cancer. Unfortunately, some men have intermediate levels (5 to 9 ng/mL) and some men can have prostate cancer with PSA levels less than 4 ng/mL. In addition, BPH and prostatitis can increase PSA levels resulting in a false positive test while some drugs may lower PSA levels and result in a false negative PSA test. Your doctor can help decide the meaning of both the PSA test and the digital rectal exam results and determine if additional tests need to be done.
Prostate Cancer Biopsy
If your doctor determines that the PSA and digital rectal exam suggest prostate cancer, the physician may suggest that a biopsy of the prostate is warranted, depending on your age, medical condition, and other factors. A biopsy is done by inserting a needle through the rectum or between the rectum and scrotal junction and then removing small samples of prostatic tissue that can be examined under a microscope for cancer tissue. The biopsy may detect and determine the aggressiveness of prostatic cancer cells.
Biopsy and Gleason Score
Biopsy samples from the prostate gland are examined by a pathologist. The pathologist then gives the tissue a grade of 1 to 5 with 5 as the worst grade of tumor pattern. Then the pathologist looks at the individual cells in the tumor pattern and grades the cell types from 1 to 5 with 5 being the most aggressive cancer cell type. The Gleason score is based on the sum of these two numbers. A Gleason score of 5 + 5 = 10 indicates a highly aggressive prostate tumor while a low score (2 + 2 = 4) indicates a less aggressive cancer.
Prostate Cancer Imaging
Prostatic cancer spread may be detected by several different tests such as ultrasound, CT, MRI, and a radionuclide bone scan. Doctors will help determine which tests are best for each individual patient.
Prostate Cancer Staging
Prostate cancer staging is a method that indicates how far the cancer has spread in the body and is used to help determine the best treatment method for the patient. Cancer that has spread to other body sites or organs is termed metastatic cancer. In terms of prostate cancer, the cancer stages are as follows:
- Stage I: The cancer is small and still contained within the prostate gland.
- Stage II: The cancer is more advanced, but is still confined within the prostate gland.
- Stage III: The cancer has spread to the outer part of the prostate and to the nearby seminal vesicles.
- Stage IV: The cancer has spread to lymph nodes, other nearby organs, or tissues such as the rectum or bladder, or to distant sites such as the lungs or bones.
Aggressive prostate cancer often reaches stage IV but others that are less aggressive may never progress past stage I, II, or III.
Prostate Cancer Survival Rates
In most individuals, prostate cancer progresses slowly through stages; about all individuals diagnosed with stage I to III prostate cancer survive 5 years or longer and with current treatments, the outlook is even better for future survival. Even stage IV has a 5-year survival rate of about 31% and this figure may also increase with advancement in treatment methods.
Treatment: Watch and Wait
"Watch and wait," is a phrase that is being used more frequently with some patients with prostate cancer. It means that if your cancer is not aggressive (based on the Gleason score and the cancer stage), treatments may be deferred and your condition periodically checked. This approach is used because the risks of urinary and sexual problems inherent in most prostate cancer treatments are serious and may be put off or avoided if the cancer is not aggressive. However, aggressive prostatic cancer is usually treated even if secondary complications of treatments are serious.
Treatment: Radiation Therapy
Radiation, focused as a beam, can be used to kill cancer cells, especially those cells that have migrated (metastasized) from the prostate gland. Beams of radiation can be used to reduce bone pain caused by invasive cancer cells. In another type of radiation therapy termed brachytherapy, radioactive pellets about the size of a grain of rice are inserted into the prostate. Both methods have side effects that can include erectile dysfunction, urinary tract problems, diarrhea, and other side effects.
Treatment: Prostate Cancer Surgery
Radical prostatectomy is the surgical removal of the prostate gland. Usually, this treatment is performed when the cancer is located only in the prostate gland. New surgical techniques help avoid damage to nerves, but the surgery may still have the side effects of erectile dysfunction and impaired urinary functions. However, these side effects may gradually improve in some patients.
Treatment: Hormone Therapy
Hormone therapy is designed to use drugs to shrink or slow the growth of cancer cells, but it does not kill the prostate cancer cells. It is used to reduce the symptoms of prostate cancer and to slow the spread of aggressive prostatic cancers by blocking or reducing the production of male hormones (androgens) like testosterone. Side effects include impotence, breast tissue growth, hot flashes, and weight gain.
Chemotherapy is designed to kill fast-growing cancer cells anywhere in the body so it is often used when aggressive prostate cancer cells metastasize to other body sites. Usually, chemotherapy is given through a special intravenous line in a series of treatments over several months. Unfortunately, chemotherapy often kills other fast-growing body cells like hair cells, mucosal cells, and cells that line the gastrointestinal tract. This can result in side effects of hair loss, mouth sores, nausea, vomiting, and other body ailments.
Cryotherapy is a treatment that kills cancer cells by freezing the cells which break apart when they are rewarmed. The treatment is less invasive than surgery, but the long-term effectiveness is still under study. Unfortunately, freezing damages nerves so many men (up to 80%) become impotent after cryotherapy.
Treatment: Prostate Cancer Vaccine
Please note that the term prostate cancer vaccine is somewhat misleading because it does not prevent prostatic cancer from developing in men. The prostate cancer vaccine is a highly individualized treatment method, designed to provide immune cells derived from a single patient’s own cells. These cells are laboratory enhanced immune cells that become capable of killing or damaging the patient's own prostate cancer cells. Like hormone therapy, this "vaccine" does not kill off all cancer cells and is currently used to slow the progression of aggressive cancers, especially those unresponsive to other treatments. Research is ongoing and perhaps this or similar methods may be developed to be more effective in the future.
Hope for Advanced Cancer
Follow-up of diagnosed prostate cancer is important. Whether the decision is to use the "wait and see" approach or any of the above-mentioned treatment methods, the prostate cancer may advance so additional tests like the PSA test or treatments may be necessary. In addition, follow-up can monitor how changes in the patient's lifestyle (appropriate diet and exercise, for example) can lower the risk of death from prostate cancer.
Coping With Erectile Dysfunction (ED)
Erectile dysfunction (ED or failure obtain or sustain an erection) is a very common side effect of most prostate cancer treatments. In some men, especially those under age 70, improved erectile function may occur within about 2 years after surgery. Additionally, the patient may benefit from various ED medications and therapies, including several types of devices specific for men with ED. Men with ED should discuss the various options with their doctor and partner to determine the best individual treatment method(s).
As stated previously, a good diet and lifestyle may help lower the risk for prostate cancer; the same is true for those men diagnosed with prostate cancer in terms of cancer recurrence. Consequently, it is appropriate to review diet and lifestyle changes:
- Increase frequency and portion sizes of fruits and vegetables
- Eat whole grains and avoid processed grains and white flour
- Reduce or stop eating high-fat dairy products and meats, especially processed meats like bacon, sausage, and baloney
- Limit or eliminate alcohol
Some research suggests that spinach, orange juice, and other foods may decrease the risk of cancer; prostate cancer patients may get additional diet and lifestyle recommendations when they follow up with their doctors.
Beware of Supplements
Prostate cancer patients and other cancer patients should be very cautious about taking supplements and other items marketed as cancer preventives or cures. Before taking any such compounds, the person should discuss the compound with their doctor. In addition, cancer patients are advised not to self-medicate or change medication dosages without first conferring with their doctor(s).