Screening for Prostate Cancer: Do You Really Want to Know?

If you are a man over 50, should you have a prostate specific antigen (PSA) blood test to test for prostate cancer?

Quite honestly, I don't know. Cancer screening tests are a great idea as long as they save lives and prevent suffering, in exchange for a small inconvenience. In the case of prostate cancer, the story is not so simple.

This year, my dad was diagnosed with prostate cancer. My dad's brush with prostate cancer and his ordeal of treatment has made the question of PSA testing come to life for me.

Here's some information about why screening is controversial: A large number of men with prostate cancer need to be treated in order to save one life. A large number of men who are treated are left with long-term, undesirable symptoms, and these side effects are not trivial. Even for experts, it is difficult to decide whether the risks of screening are worth the benefits. 

Prostate cancer is incredibly common. One out of every six men can expect to have prostate cancer in his lifetime, and about one out of every 32 men dies of prostate cancer.  Prostate cancer is one of the top four most lethal cancers in the United States, in terms of the number of men that it kills. It can cause miserable bone pain, if it spreads. Despite these real issues, prostate cancer is a "low risk" cancer. It isn't a lethal cancer in most men who have it.

According to current estimates the risk of dying from early stage prostate cancer if it is not treated is about 4% to 7%.   If it looks somewhat more threatening under the microscope (if it is given a "Gleason score" by the pathologists of 7 to 10), an untreated cancer would be more likely to kill a man—probably, the majority of these men would die of their cancer.  Deciding to get treatment for prostate cancer is an easy process for most men who have a cancer with a higher Gleason score. But you have to consider what you would do about an early stage cancer—this is, after all, the stage of cancer that is most often found with the PSA test.

If you have cancer found by a PSA test and it is an early stage cancer, you face a dilemma. The odds are about 13 to 1 that your cancer will stay quietly contained inside your prostate, allowing you to live to your full age and die of an unrelated cause.  Given these odds, is it worthwhile even having the PSA test?  And if an early cancer is detected by PSA testing, should you go through treatment for your cancer?

Most men do. "Living with cancer" is too anxiety provoking for most of us. But there are major side effects from the usual treatments, and none of the treatments is a cake walk. Most men don't have a sense of this before they begin to have PSA testing.  Some men do choose to forego treatment even after learning they have prostate cancer.  It's often a reasonable choice since treatment of the earliest tumors is not clearly beneficial.  In this situation, follow-up testing of the PSA is highly recommended because a rising PSA may be an indication of a growing cancer.

Sitting through sessions with my dad and his urologist as we considered different treatment options was sobering. All of the treatments would give him good odds of surviving his cancer.  But none of the options sounded very pleasant. Here are the three most popular treatment options, and the various burdens that come with them:

Surgery (prostatectomy):

• Before having surgery, men need to go through an anxiety-provoking waiting time of 6 to 8 weeks.  That's because the diagnosis is typically made by a needle biopsy of the prostate and the biopsy causes some inflammation. Inflammation, in turn, can make surgery more technically difficult so surgeons want to wait until, the inflammation resolves.
• The surgery itself can take up to four hours.  It is not a simple surgery, and it is not a surgery without risk. My father had a heart attack during his surgery—he was lucky he survived. The chance of dying during a prostatectomy operation is about 1 in 200. The recovery time from this operation can require roughly two months out of work.
• Nearly every man who goes through this surgery wets himself for at least a few months after the operation. Before surgery, the prostate sits under the bladder like an oversized knot at the bottom of a water balloon. If you slice the knot off a balloon, or you slice the prostate off the bladder, you can expect to be wet.
• Most men are able to regain control over their urinating after the base of the bladder adapts to its new anatomy. But about 35% of men have incontinence that is long-term, at least at times, when they sneeze, cough, or lift heavy things.
• The vast majority of men are impotent after this surgery, even with modern "nerve-sparing" techniques.

External beam radiation (radiation from a machine):

•  To have this treatment, you need to go to appointments at your medical center every day, Monday through Friday, for 6 to 8 weeks.
• Many men—at least 20%—have symptoms from the radiation during the treatment process. Symptoms that begin along with the radiation treatments include, an urgent feeling that you will have a bowel movement, frequent bowel movements, painful spasms in the rectum, and diarrhea.  Rectal bleeding is quite common, but is usually self limited.  It can, however, be the main side effect of radiation.
• Long-term rectal or bladder side effects occur in less than 10% of men, but they can be unpleasant (rectal bleeding, rectal spasms, an urgent feeling with bowel movements, diarrhea, and urinary incontinence).
• Impotence occurs in up to half of men who have this treatment, even though it doesn't usually begin right away.
• If you treat your cancer with radiation, you don't have the confidence of knowing after your treatments whether the cancer has spread to the lymph nodes or not. This knowledge only comes from surgery. However, the presence of lymph node involvement is quite uncommon, especially if the PSA is less than 10.

Brachytherapy (radiation from implanted radioactive beads):

• This form of radiation spares men the frequent visits to a medical center that are required for external beam radiation treatments. However, it does require a surgical procedure—with anesthesia—to have radioactive beads placed inside the prostate.
• For a while after the beads are implanted, a man is radioactive. Grandchildren are not allowed to sit on your lap for two months. For my dad, who coped with his cancer diagnosis by surrounding himself by his family, this was an unacceptable requirement.
• The side effects (short-term and long-term) are the same as for external beam radiation; urinary difficulties are particularly common.
•  Like external beam radiation treatment, you don't have the confidence of knowing after your treatments whether the cancer has spread to the lymph nodes or not.

Deciding on a prostate cancer treatment is not a casual process. Black men and men with a family history of prostate cancer are more likely to have aggressive cancers, so for these men screening for prostate cancer may be beneficial, but we still do not know for sure.  For all other men, if a cancer is found during a PSA screening, there is a large risk that your quality of life could be lowered but a small chance that your life will be made longer and—if you avoid cancer symptoms—more comfortable. Some men decide they would rather not know. About 64% of men either opt for screening, or are screened by their doctors with little discussion.

What about you? Do you choose to have your PSA tested? Did your doctor help you to clearly understand the pros and cons before testing? These pros and cons cause even the experts to be unsure about the value of prostate cancer screening.

Mary Pickett, M.D., is an Associate Professor of Medicine at Oregon Health & Science University where she is a primary care doctor for adults. Her field is Internal Medicine. She is also a Lecturer for Harvard Medical School and a Senior Medical Editor for Harvard Health Publications.

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