What is the 4K Score Test?

The 4Kscore test is a simple blood test that detects high risk, aggressive prostate cancer. It measures four prostate protein (prostate-specific kallikreins) levels in your blood including total PSA, free PSA, intact PSA, and human kallikrein 2 (hK2). The results are combined in an algorithm with patient age, digital rectal exam and prior negative biopsy to give physicians a personal score for each patient. 


The 4Kscore helps doctors clarify the biopsy decision-making process by determining a patient specific probability for finding aggressive, Gleason score 7 or higher prostate cancer upon biopsy. It predicts the risk percent score from less than one percent to greater than 95 percent of a man having aggressive cancer in a prospective biopsy. 

Who needs the 4K score test? The 4Kscore test is for any man concerned about his risk for high-grade, aggressive prostate cancer. It is especially useful when considering having a prostate biopsy. The most common reasons a man might have a prostate biopsy include having a family history of prostate cancer, an elevated PSA or high PSA, abnormal results from a digital rectal exam, or a prior negative biopsy. 

How does it work? The PSA test does not clearly distinguish between prostate cancer and less serious conditions. It is simply not specific for prostate cancer. Controversy surrounds the PSA test because it has been thought to result in many men having unnecessary prostate biopsies. There are more than one million prostate biopsies performed in the United States each year. Only 20 percent detect aggressive prostate cancer while 80 percent of prostate biopsies are either negative or detect a low-grade, non-life threatening form of prostate cancer. 

The benefits of the 4Kscore test is that it helps reduce the number of unnecessary biopsies, by measuring a man’s risk of having aggressive prostate cancer. If that risk is low, yoururologist may decide not to do a prostate biopsy. It also avoids the associated pain and complications such as bleeding and infection that may result in having a prostate biopsy. You may also be able to avoid treatment if the risk for prostate cancer is low and non-life threatening. 

Where can you get the test? The test was developed by OPKO Lab in Nashville, Tennessee and was released in March 2014. It must be ordered and reported by a physician. It is not currently covered by private insurance (Medicare, Medicaid) and costs $395. The test may be reimbursable by a Health Savings Account.