On Father’s Day last month, Sen. John Kerry, D-Mass., and radio shock jock Don Imus co-authored an op-ed for the Boston Globe in which they argued that men needed to be sure they received regular preventive screening check-ups for prostate cancer. Both men are prostate cancer survivors.
“Screening for prostate cancer is the only option,” they wrote.
But therein lies a big, big problem — and yet another medical controversy. Just a few days after that op-ed ran, a review article in the medical journal CA: A Cancer Journal for Clinicians reported that the PSA blood test, routinely used to screen for prostate cancer, saves few lives, wastes money and often leads to risky and unnecessary treatments.
An editorial that accompanied the review noted that not a single well-designed clinical trial has yet to show that PSA screening reduces the death risk from prostate cancer.
“PSA screening has remained a controversial topic,” wrote the editorial’s authors, with considerable understatement.
What the test is
The PSA test, which measures the blood levels in men of a protein called prostate-specific antigen, was originally developed to monitor the progress of patients after treatment for prostate cancer. This disease claims the lives of more than 27,000 men in the United States each year, making it the second leading cause of cancer deaths (after lung cancer) in American men. PSA levels increase when cancer is present, but they also increase with certain benign prostate conditions — and with age. In addition, most prostate cancers grow very slowly and remain confined to the prostate gland, never causing any health problems. Thus, as the authors of both journal articles pointed out, PSA screening has led to the overdiagnosing and overtreatment of prostate cancer. This is no small matter, for the treatments for prostate cancer can have serious adverse effects, including impotence and incontinence.
Today, more than 55 percent of American men aged 50 or older undergo this screening test annually.
On the topic of benefits versus risks, the editorial was unambiguous:
The real impact and tragedy of prostate cancer screening is the doubling of the lifetime risk of a diagnosis of prostate cancer with little if any decrease in the risk of dying from this disease. In 1985, before PSA screening was available, an American man had an 8.7% lifetime risk of being diagnosed with prostate cancer and a 2.5% lifetime risk of dying from the disease. Twenty years later, in 2005, an American man had a 17% lifetime risk of being diagnosed with prostate cancer and a 3% risk of dying from prostate cancer.
The editorial concluded that the collective data from studies “cannot justify mass screening and indeed appear to justify support for a recommendation against mass screening.”
Wrote the authors:
For nearly 2 decades, testing has been based on blind faith in early detection as opposed to being based on evidence of a decrease in mortality as observed in well-designed clinical trials. Prostate cancer screening and the treatment of early stage disease is also a profitable industry. Despite discouraging findings from now 4 randomized trials of prostate cancer screening, much of the controversy surrounding the use of PSA as a population screening test remains unresolved. The high prevalence of PSA testing will be difficult to reverse. If we are to stem the spiraling costs of health care, we must move toward the use of evidence-based rather than the faith-based or profit-based practice of medicine.
What should men do about the PSA test? The editorial recommends talking about the issue with your physician and then making a “shared decision.” I suggest that before you go in for that talk, you read both the review and the editorial in CA: A Cancer Journal for Clinicians. The full-text versions are available free at the links I provided above.