News Review From Harvard Medical School -- Study Sees No Benefit in Prostate Surgery
A new study of men with early prostate cancer found no difference in death rates whether they received surgery or no treatment. The study adds to recent evidence that prostate cancer may be overtreated in the United States. The study included 731 men with early prostate cancer. Their average age was 67. They were randomly assigned to have immediate surgery or no treatment. People in each group lived an average of about 13 years after the study began. Nearly 6% of men in the surgery group and just over 8% in the no-treatment group died of prostate cancer. That difference was small enough that it could have been caused by chance. But there was some evidence of benefit for men with a score of 10 or higher on the prostate-specific antigen (PSA) test. Prostate cancer deaths were 33% lower for men with these higher scores who had surgery rather than no treatment. About 1 out of 5 men assigned to no treatment decided to have treatment later. The New England Journal of Medicine published the study. The New York Times News Service wrote about it July 19.
By Robert H. Shmerling, M.D.
Harvard Medical School
What Is the Doctor's Reaction?
Imagine that your doctor told you about a commonly ordered screening test for cancer, but wasn't sure you should have it.
And what if you were just diagnosed with cancer, but your doctor said you needed no treatment for it?
In the case of prostate cancer, both of these situations are increasingly likely.
The common screening test is the PSA (prostate-specific antigen). It's a protein produced by prostate tumors. The blood test to measure PSA has long been offered as a routine screening test for prostate cancer. But more recent studies question whether it's useful. And treatment for newly diagnosed prostate cancer is not always helpful.
How can this be? It's because of some unique features of prostate disease and the men who have it:
- As men age, nearly all of them develop an enlarged prostate. Usually they don't have cancer.
- A high PSA is common with an enlarging prostate, whether cancer is present or not.
- Prostate cancer often grows so slowly that it poses no threat to a man's health.
- Men who get prostate cancer tend to be older. Other health problems often cause trouble (or even death) well before prostate cancer detected by PSA screening does.
- Treatment of prostate cancer may be linked with major side effects such as problems with urine control and sexual function.
When all of these factors are taken into account, routine screening and early treatment may not be useful.
This new study is the latest to question whether it's useful to treat prostate cancer in its early stages. In the study, 731 men were randomly assigned to receive surgery to remove the prostate gland or no treatment. During the next 12 years, there was almost no difference between these groups in rates of death from prostate cancer or other causes. Nearly 1 out of 5 men who had surgery suffered problems such as a wound infection or bleeding.
However, there is at least one important caution to keep in mind about this study: It was much smaller than planned. It was supposed to recruit 2,000 men. But it was hard to enroll men who would leave it up to chance whether they were assigned to treatment or no treatment for their newly diagnosed prostate cancer.
A larger study might have determined that some men do benefit from early surgery. Even in this study, there was a hint of benefit for those with the highest PSA scores and those with the most aggressive tumors.
What Changes Can I Make Now?
The most recent guidelines about PSA screening reflect the notion that it is not clearly helpful. Increasingly, doctors are advised to leave the decision about PSA screening up to the patient after discussing its uncertain benefits. So don't be surprised if that's what happens the next time you see your doctor.
Talk to your doctor about any factors that may increase your risk of prostate cancer. These risk factors do matter. For example, advanced age and a family history of the disease are linked with an increased risk of prostate cancer. African-American men have a higher risk than white men.
You can take steps that may prevent prostate cancer or its complications. For example:
- If your prostate is enlarged, take a medicine that shrinks it. The overall benefit is uncertain. However, there is some evidence that drugs such as finasteride (Proscar) may reduce the risk of prostate cancer.
- Change your diet. A low-fat diet that's high in fish and lycopene may lower the risk of prostate cancer. Lycopene is found in watermelon, cooked tomatoes and over-the-counter pills.
- Have a prostate examination. Your doctor can perform a rectal exam to detect whether the prostate is enlarged or has any growths that might be cancerous.
- Have a biopsy if your prostate exam finds a growth or something else abnormal. A biopsy showing cancer may lead to surgery, radiation, hormone treatment or a combination of these. Or, as this new study suggests, no treatment may be needed. The decision will depend on your preferences and the details of the biopsy results (such as the type of tumor and whether it has spread).
- Let your doctor know your preferences. Given the uncertainty about the value of routine screening for prostate cancer and treatment of early disease, your opinions matter. Some men choose aggressive treatment to remove all traces of the cancer. They are willing to accept the risk of treatment-related side effects. Other men would rather avoid surgery if at all possible.
What Can I Expect Looking to the Future?
A major focus of current research is figuring out how to know which prostate cancers need treatment and which aren't even worth diagnosing. Researchers are looking at new screening approaches, such as measuring different forms of PSA, and new imaging techniques. In the future, the results of these studies should help us figure out whom to screen, how to screen and, most importantly, what to do with the results.