> Health and Disease > Cancer > alternative medicine for cancer

PSA: Prostate Scandal Alert
by author Julian Whitaker, MD

Six years ago, Mike sat down with his doctor during his yearly checkup to go over the results of his blood tests. Everything looked good with one exception: His PSA was moderately elevated.

Mike was referred to a urologist for further evaluation who ordered a biopsy, found a malignancy, and recommended surgery. Mike underwent radical prostatectomy (removal of his prostate gland), and today, at age 75, Mike is alive, well, and convinced that he owes his life to the PSA test that found early-stage prostate cancer.

Mike is not alone. According to the Prostate Cancer Research Foundation of Canada, 19,000 Canadian men are diagnosed with prostate cancer every year, and many of them opt for surgery, radiation, or hormonal treatment. Men who go through this often feel, as Mike does, that early detection with PSA saved their lives. But did it?

What’s a PSA Test?

Prostate-specific antigen (PSA) is a protein produced by the epithelial cells lining the prostate, a small, doughnut-shaped gland that wraps around the urethra and produces the fluid part of the semen. Levels of PSA, which can be measured by a simple blood test, rise in the presence of prostate diseases such as prostatitis (inflammation of the prostate), benign prostatic hyperplasia (BPH) (age-related enlargement of the prostate), and cancer.

When this test burst onto the scene 18 years ago, it was viewed as a godsend by physicians and patients alike. Finally a screening test was available for men that, like mammography for women, would find their most common type of cancer in its early, treatable stages. Experts espoused routine screening, and its popularity soared. But like many tests, drugs, and surgical procedures that are embraced by mainstream medicine, PSA testing has not lived up to the hype. In fact, it may do more harm than good.

Is the PSA Screen Too Fine?

Thomas Stamey, MD, professor of urology at Stanford School of Medicine, is often referred to as the “father of PSA.” He was involved in the first study linking elevations in PSA to prostate cancer, and for two decades has remained at the forefront of PSA research, publishing more than 100 studies and journal articles on the subject. Dr. Stamey now believes that PSA testing as a screening tool for prostate cancer has outgrown its usefulness and has stated outright that the “prostate-specific antigen era… is over for prostate cancer.”

He explains that in the early years of PSA testing, it was a fairly reliable tool for diagnosing prostate cancer. In his initial research, which was published in the New England Journal of Medicine in 1987, the size of prostate tumors removed by radical prostatectomy was compared to PSA levels before removal, and there was a reasonable relationship between the two. In almost half of the cases studied, PSA was predictive of size and severity of prostate cancer.

Today, however, it’s a different story. In a follow-up study, published in 2004 in the Journal of Urology, Dr. Stamey’s research team reviewed 1,317 specimens from radical prostatectomies performed from 1983 through 2003 and again compared preoperative PSA levels to tumor aggressiveness. They found that in the cases from 1983 through 1988, there was a reasonable correlation between blood levels of PSA and prostate cancer, reflecting the results of the 1987 study. Yet in the cases from 1999 through 2003, there was little connection between PSA and prostate cancer size and severity: a relationship was noted in only two percent. In fact, the only parameter clearly linked with PSA levels was overall prostate weight, leading the authors to conclude, “In the last 5 years, serum PSA has only been related to benign prostatic hyperplasia.”

Why such a dramatic difference? Because we’ve taken PSA screening to ridiculous extremes. Eighteen years ago, the majority of prostate cancers were detected by digital rectal exam. (A physician inserts a gloved finger into the rectum to feel the prostate; hard lumps are indicative of tumor growth.) These tumors were large enough to generate appreciable levels of PSA, 25 nanograms per milliliter (ng/mL) on average. These cancers had clinical significance and needed to be treated.

Julian Whitaker, MD, practises medicine at the Whitaker Wellness Institute in Newport Beach, California (whitakerwellness.com), and writes the monthly newsletter Health & Healing (drwhitaker.com).

Source: alive #272, June 2005