There are over 1 million men who have a prostate biopsy each year. Many of the biopsies are negative. What can a man do who has an elevated PSA level and a negative biopsy to be certain that he doesn’t have prostate cancer and avoid having a second biopsy?
Lots of controversy surrounds the standard PSA (prostate-specific antigen) screening test for prostate cancer, which is unreliable and not specific for the disease. This uncertainty has prompted many men to ask, “Is there a better test for PSA?” Fortunately, there are options which, while they don’t replace the current PSA test, can provide significantly more reliable, actionable information.
The PSA test involves a blood draw and measuring the level of the blood protein, prostate specific antigen. Currently, men whose PSA test levels are between 4 ng/mL and 10 ng/mL typically are told they should consider getting a prostate biopsy. However, an elevated PSA can be caused by many different benign conditions such as benign enlargement of the prostate gland, a prostate infection or simply lifestyle habits, which means a biopsy would be an unnecessary invasive procedure.
Why we need more accurate testing?
Approximately 1.3 million prostate biopsies are performed annually, and less than one third of them reveal cancer. While that sounds like good news on one hand, on the other hand it means that two thirds of those biopsies may not have been necessary and/or these men have negative biopsy results but other clinical risk factors for prostate cancer such as a family member who has prostate cancer or being an African-American man who have a slightly greater risk for prostate cancer than a Caucasian man.
If you have been in this situation, you probably know how frustrating and confusing it can be. What should you do? Have a repeat biopsy or choose to have more tests? The uncertainty of having a hidden prostate cancer can lead men to get repeat biopsies, which can be associated with an increased risk of infection, hospitalization, emotional trauma, and significant costs.
Fortunately, some progress is being made in the realm of better testing for prostate cancer and in determining whether a prostate biopsy is necessary. In this blog I will discuss the PCA3 test that may be helpful and prevent additional biopsies and additional psychological anxiety.
PCA3 is an acronym for Prostate CAncer gene 3. Prostate cells have PCA3 genes that are responsible for making this prostate cancer-specific protein. Prostate cancer cells produce higher levels of PCA3 than do healthy cells, and when the level of PCA3 protein is high, it leaks into the urine, where it can be measured. Unlike the PSA test, PCA3 is not affected by benign prostatic hyperplasia (enlarged prostate) or other noncancerous prostate conditions such as prostatitis.
To take the PCA3 test, you must first have a digital rectal examination (DRE), which stimulates the PCA3 to enter the urine. Then you must immediately provide a urine sample. Typically, it takes 1 to 2 weeks to obtain the results of the PCA3 test. For diagnostic purposes, the higher the PCA3 score, the more likely a man has prostate cancer. When the PCA3 score is used to help with treatment, the higher the score, the more aggressive the prostate cancer is likely to be.
The Food and Drug Administration approved the PCA3 test in 2012. Physicians can use the PCA3 score, in addition to DRE and PSA test, to help them make treatment decisions. For example, knowing a man’s PCA3 score can be helpful when:
- Men have a family history of prostate cancer
- Men have a positive biopsy, because their PCA3 score can provide additional information about how aggressive the cancer may be and therefore, be helpful in determining which treatment approach is best
- Men have an elevated PSA or a suspicious DRE and are considering a prostate biopsy
- Men have a negative result on their biopsy but the doctor is still uncertain about the presence of cancer
- Men have a positive result on their biopsy and they and their doctor want to better understand how aggressive the cancer is
- Men who have early, nonaggressive prostate cancer and have chosen active surveillance want to monitor any possible cancer progression
How effective is the PCA3 score in detecting prostate cancer? This question was addressed in a study involving 859 men who were scheduled to undergo a prostate biopsy. The authors found that use of the PCA3 test improved over-detection of low-grade prostate cancer and under-detection of high-grade cancer. Cost of the PCA3 test is about $450. The test is paid by most insurance companies including Medicare.
Bottom Line: Prostate cancer is the most common cancer in men and the second most common cause of death in men. The PSA test is a good screening test for men between the ages of 50 and 70. However, there are false positive results with consequences of unnecessary prostate biopsies or may result in unnecessary repeat prostate biopsies. The PCA3 test is helpful in identifying prostate cancer or helpful in reassuring a man that he doesn’t have prostate cancer and can avoid a repeat biopsy. For more information, speak to your urologist.