If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.
Prostate cancer is the second leading cause of cancer deaths in men behind lung cancer. Though most men with prostate cancer will survive, the fact that even a successful treatment can result in loss of sexual function and incontinence makes prostate cancer a scary diagnosis.
There are many treatments available, and advances over the past decades have resulted in greater survival rates than ever before. Even the dreaded side effects are now less common and less severe. However, the available treatments are far more successful when prostate cancer is diagnosed at an earlier stage, and early discovery of prostate cancer can mean the difference between a simple procedure with excellent results—or one that is not.
It seems logical that early detection could only be a benefit to all men as they age, but It turns out that screening for prostate cancer is a more complex and controversial issue as we’re about to see. Whether to screen and how to screen must be individualized for each man and take a number of factors into consideration.
This article aims to give you the empowering information you need when starting a conversation with your healthcare provider.
- Screening for prostate cancer is a complex and controversial issue.
- In some cases, overdiagnosis leading to overtreatment can be more harmful than the disease itself.
- Different medical societies promote differing recommendations around screening.
- Men should work closely with their healthcare provider to decide how, when, or if to screen for prostate cancer.
A primer on cancer screening
The World Health Organization (WHO) defines disease screening (WHO, 2017) as “the presumptive identification of unrecognized disease in an apparently healthy, asymptomatic population by means of tests, examinations or other procedures that can be applied rapidly and easily to the target population.”
In plain English, this means screening people without symptoms of a disease with some type of test in order to detect the disease and treat it earlier. This seems like a no-brainer. What could be wrong with a test to catch a disease and treat it at an earlier stage? Well, it’s not as simple as it seems. Covering the topic of disease screening could be the subject of an entire book, but here are a few basics.
For a screening test to be useful it must have some basic traits:
- The ability to detect a disease early.
- The early initiation of treatment for the disease must make a difference in outcomes. (Sometimes treating a disease earlier in its course doesn’t improve survival or even lessen suffering from the disease.)
- It must be easy to administer and be acceptable to the screening population.
- It should have an acceptable false positive rate. False positives are positive test results in people who don’t have the disease. Tests with a low false positive rate are said to be highly specific.
- It should have an acceptable false negative rate. False negatives are negative test results in people who do have the disease. Tests with a low false negative rate are said to be highly sensitive.
There is generally a trade off between sensitivity and specificity. When one goes up, the other goes down. Screening tests should have a good balance of sensitivity and specificity.
The dilemma of prostate cancer screening
Currently, there are two widely available methods for prostate cancer screening:
- A digital rectal exam (DRE) is when the physician feels the prostate with his finger and inspects it for lumps or areas that are harder or softer than normal.
- A blood test to measure prostate specific antigen (PSA), a protein produced by prostate cells that increases in people with prostate cancer.
These tests can also be used together. Both tests can detect prostate cancer in men without symptoms, but they have significant drawbacks, too.
The potential benefits are preventing death from prostate cancer and decreasing the incidence of metastatic prostate cancer, which screening has been shown to do.
One of the drawbacks are the tests’ accuracy. The DRE has been shown not to be very sensitive or specific (Naji, 2018). This means many people who test negative still have the disease and many people who test positive do not have the disease. PSA screening is more sensitive and specific (Mistry, 2003), but there are still potential drawbacks. One of the major drawbacks is that prostate cancer screening with PSA has not been found to decrease mortality (death) (Fenton, 2018) even though more people are diagnosed with prostate cancer if they are screened.
About 20%–50% of PSA screen-detected prostate cancer represents overdiagnosis due to overdetection. Overdetection (Brodersen, 2018) has been defined as “the identification of abnormalities that were never going to cause harm, abnormalities that do not progress, that progress too slowly to cause symptoms or harm during a person’s remaining lifetime, or that resolve spontaneously.” This means that people are diagnosed with a disease that would have never caused them problems.
Overdiagnosis is likely to result in overtreatment. Simply put, overtreatment refers to treating a disease that would have never caused problems in a person’s lifetime. Overtreatment comes with the risks of causing treatment-related side effects in people who didn’t need treatment in the first place. These risks include infections, bleeding, and urinary problems due to biopsies, as well as erectile dysfunction (ED), urinary incontinence, and fecal incontinence from a range of treatments. In some cases, the cure or treatment can be worse than the disease.
There are also still outstanding questions about prostate cancer screening. One important question is whether the risk–benefit ratio is different in men with a higher risk of prostate cancer. This includes African Americans and men with a family history of prostate cancer. Another question is whether there is a lower risk of harms today since more men and their healthcare providers are opting for active surveillance/active monitoring. Active surveillance/active monitoring is often used in stage I or stage II, the earlier stages of the disease. Over time patients undergo physical exams, PSA tests, and often prostate ultrasounds and/or biopsies. healthcare providers only begin treatment if there is evidence that the cancer is progressing. This approach may improve the risk–benefit ratio as well.
Lastly, is there a way to predict more accurately which men have higher risk disease (who should be treated) vs men with lower risk disease (who can be monitored)? This may also reduce the adverse effects of overtreatment.
Prostate cancer screening recommendations
As you can see, prostate cancer screening is far from being a no-brainer. Different specialty organizations have changed their recommendations over the years.
The American Urological Association (AUA) recommends (Detection, 2018) that men aged 55–69 should engage in shared decision-making with their healthcare providers when deciding whether to screen for prostate cancer.
Shared-decision making is a process by which healthcare providers share the best available evidence, weighing the risks and benefits, so that a man can make an informed decision with his healthcare provider’s support. The AUA also recommends that decisions about screening men aged 40–54 be individualized, with risk factors for prostate cancer (e.g., family history, African American) taken into consideration. The AUA does not recommend routine screening before age 40 or after age 70. Screening is performed by measuring prostate-specific antigen (PSA) levels, sometimes with a digital prostate exam.
The United States Preventive Services Task Force (USPSTF) has recommendations (USPSTF, 2018) that are very similar to the AUA. The American Academy of Family Practice (AAFP) recommends (AAFP, 2018) against routine screening for prostate cancer based on the small benefits and larger risks of screening. The AAFP is unclear about whether healthcare providers should start a conversation with men about screening or should only screen if someone asks for it specifically.
While different organizations’ prostate cancer screening guidelines differ in certain respects, all make it clear that screening decisions should be individualized for each man. Risk factors and personal values are important factors when choosing what to do as is a trusting relationship with your healthcare provider.