U.S. Govt. Panel Says ‘NO’ to Routine
PSA Screening in Men Older than 75
Source: Original Article (Ann.Int.Med),
U.S. Govt. websites, and various news agencies
August 5, 2008 – Men older than 75 years should not undergo PSA screening for prostate cancer, according to findings of a high-level government panel published in the August, 2008 issue of Annals of Internal Medicine. The panel, the U.S. Preventive Services Task Force (USPSTF), is an independent panel of experts in primary care and prevention. It is the highest level governmental body charged with the task of making recommendations for clinical preventive services. The task force operates under the auspices of the Agency for Healthcare Research and Quality, which is a branch of the Department of Health and Human Services.
A summary of the panel recommendation is provided here.
Why draw the line at 75? The average 75 y.o. man currently has about a 10-year life expectancy. Localized prostate cancer has a 5-year survival rate approaching 100% without treatment (SEER). The longevity benefit from curative treatment of localized prostate cancer thus begins to accrue more than 5 years after diagnosis. In other words the benefit is a delayed one. Consequently, few men age 75 years or older would derive any longevity benefit from surgery or radiation, or so goes the argument of the Task Force panel.
The delay in treatment benefit is seen in data from the landmark Scandinavian study of Anna Bill-Axelson, et al, comparing radical prostatectomy with watchful waiting. A key figure from that study is shown here.
However, the USPSTF recommendation applies to populations, but not individuals, for several reasons:
- Although the average 75 y.o. man may have a 10-year life expectancy, the healthiest upper quartile of 75 y.o. men have a 15-year life expectancy. Thus, at least 25% of 75 y.o. men would derive a considerable longevity benefit from cure of prostate cancer.
- Some prostate cancers are high-grade malignancies and may progress faster than those of low grade. Thus, the 5-year mortality rate for the worst cancers might be considerably higher than zero.
- Removal of the prostate, in the active arm of the Scandinavian study, also prevented morbidity of prostate cancer, ie, metastatic disease and local progression. In fact, preventive impact of prostatectomy was greater for these two variables than the mortality impact.
- Removal of the prostate also reduces the anxiety factor, since it provides definitive information relative to stage and grade of the disease, thus allowing for improved prediction of outcome. The anxiety factor has been studied most extensively in men undergoing ‘Watchful Waiting’ and is often the active-treatment impetus in this situation.
- Members of the USPSTF panel making the recommendation are experts in preventive care at the population level, rather than providers of care for individual patients with prostate cancer. Not a single urologist was included among the 16 panel members!
Reactions to the Task Force recommendations were brisk and strong, both pro and con, and widely reported in the lay press. Comments by various experts ranged from "appropriate" to "a form of age discrimination." A few are reproduced here:
Prostate Cancer Facts
An estimated 218,890 U.S. men received a prostate cancer diagnosis in 2007, and 1 of 6 men in the U.S. will receive the diagnosis in his lifetime. An estimated 27,350 men died of prostate cancer in the United States in 2006. The median age of death from prostate cancer from 2000 through 2004 was 80 years; the average age at diagnosis was 68. 71% of deaths occurred in men older than 75 years. African-American men have a substantially higher prostate cancer incidence rate than white men (217.5 vs. 134.5 cases per 100 000 men) and more than twice the prostate cancer mortality rate of white men (56.1 vs. 23.4 deaths per 100,000 men).