Test may diagnose prostate cancer more accurately

A study in the December 2015 issue of The Lancet Oncology found that a new test, called STHLM3, is more helpful at detecting aggressive cancer than traditional tests for prostate-specific antigen (PSA).

The STHLM3 test is a blood test that analyzes a combination of six protein markers, more than 200 genetic markers, and various clinical data, such as age, family history, and previous prostate biopsies.

Currently, the PSA test is used to help diagnose possible prostate cancer, but PSA screening has long been controversial because it cannot distinguish prostate cancer from benign conditions like prostate enlargement. PSA tests also can give a "false negative" reading and miss about 20% of all prostate cancers.

The study included 58,818 men ages 50 to 69. Both the STHLM3 and PSA tests were performed on all participants and then compared. The STHLM3 test found aggressive cancers in men with low PSA values (1 to 3 ng/ml) that often go undetected, and about one-third of the male population between the ages of 50 and 69 are in this PSA range, says lead researcher Dr. Henrik Grönberg of the Karolinska Institutet in Sweden.

The STHLM3 test is now available in Sweden, and the researchers hope to expand it to other countries, including the United States, in the near future. Finding more prostate cancer does not necessarily translate into fewer deaths from cancer. Long-term studies are still needed to prove if this test is a useful screen.