Though not perfect, blood test for prostate cancer is still recommended

The prostate-specific antigen (PSA) test is a common way to detect prostate cancer in its earliest stages. The exact number of a dangerously high PSA count is constantly under debate and varies among men in different age groups. Despite its imperfections, WUSM urologic surgeon Arnold Bullock still recommends the test be taken annually as part of a healthy prostate health regimen for men over 50.

Read more about the PSA test and other ways to detect prostate cancer in the following St. Louis Post-Dispatch article by Kay Quinn.

PSA test for prostate cancer raises questions

(Republished with permission from the St. Louis Post-Dispatch. This article originally ran in the Health & Fitness section on Monday, Nov. 29, 2004)

By Kay Quinn

Almost 30,000 American men will die of prostate cancer this year.

That statistic leads some physicians, including Dr. Arnold Bullock, a urologic surgeon at Washington University School of Medicine, to recommend annual blood tests for prostate cancer and digital rectal exams for men over 50. The screenings may be recommended even earlier for African-American men and others at high risk.

But the blood test to measure PSA – prostate-specific antigen – is itself the subject of controversy. Clinical studies have shown that men can have low PSA levels but still have prostate cancer. Even biopsies of the prostate can indicate a man is cancer-free when he’s really not. As a result, the American Cancer Society advises men to discuss with their doctor whether to have a PSA test.

The history of the PSA test is an interesting story, one that reflects the changing nature of medicine. Bullock says that when urologists at Washington University began routinely testing PSA in the late 1980s and early 1990s, they considered men at risk for prostate cancer if their reading was above 2.8 nanograms of prostate-specific antigen per milliliter of blood.

But Bullock says that led to unnecessary biopsies, so the number was adjusted up to 4.0. Seven years ago, however, Bullock and his colleagues reset the number at 2.5, but he admits controversy remains about where the ideal point should be set for early detection of prostate cancer.

Today, he and his colleagues recommend biopsies in men ages 50 to 59 with readings higher than 2.5, in men between 60 and 70 with readings higher than 4.0, and in men older than 70 with readings more than 6.0.

But what Bullock finds even more troubling than the inaccuracies sometimes associated with the PSA is what he calls the myth surrounding prostate cancer. He says too many people believe this type of cancer is always benign and slow-growing. Though the PSA test may not be perfect, Bullock remains an advocate because he considers it one of the best tools available for finding prostate cancer in its earliest, and most treatable, stage.

He also believes prostate cancer is much more prevalent than most people think. Bullock cites statistics that show 30 percent of men over 50 show evidence of prostate cancer on autopsy.

What’s the bottom line? Bullock says you shouldn’t rely on the PSA test to give you the full picture regarding your prostate health. Many urologists agree the best screening advice is to see your doctor at least once a year for a 20-second digital rectal exam and a PSA blood draw. Then, along with a review of your medical history, and in consultation with your doctor, decide what to do with that information.

Kay Quinn is a reporter and anchor at KSDK (Channel 5).

Copyright 2004 St. Louis Post-Dispatch, Inc.