Adapted from the NCI Cancer Bulletin.
A new study confirms previous research showing that screening for prostate cancer with the prostate-specific antigen (PSA) test has led to overtreatment of many prostate cancers, including aggressive treatments in older men considered to be at low risk for progression of the disease. The results appeared in the July 26, 2010 Archives of Internal Medicine.
The researchers found that 77 percent of men with a serum PSA level of 4.0 nanograms per milliliter (ng/mL)—the level at which a prostate biopsy is often recommended—or lower underwent either complete removal of their prostate, known as a radical prostatectomy, or radiation therapy. This treatment occurred even though more than half of these men were considered to be at low risk of disease progression based on commonly used factors, such as the Gleason score and the extent of local tumor spread.
Despite evidence that suggests older men are less likely to have a survival benefit from surgery or radiation compared with more conservative treatments, age was not a barrier to low-risk men receiving aggressive treatment. Nearly 69 percent of men age 65 to 74 and approximately 40 percent of men 75 and older underwent either surgery or radiation.
“Our study demonstrates that Gleason score, PSA level, and risk stratification does not appear to substantially influence the decision to have attempted curative therapy,” wrote lead investigator Dr. Yu-Hsuan Shao of the Cancer Institute of New Jersey and colleagues.
To conduct the study, the researchers used data from NCI’s SEER registry to identify nearly 124,000 men who were newly diagnosed with prostate cancer between 2004 and 2006. Of these men, 14 percent had PSA levels of 4.0 ng/mL or lower. Rates of radical prostatectomy and radiation were actually higher among men whose PSA levels were at or below 4.0 ng/mL than among men whose PSA levels were between 10.1 and 20.0 ng/mL.
“It has been documented that men who receive any treatment have increased risk of treatment-related adverse effects,” Dr. Shao and colleagues wrote. “Therefore, it is critical that patients be counseled about treatment-associated adverse effects and benefits when they are deciding about therapy.”
In an accompanying editorial, Drs. Richard Hoffman of the University of New Mexico and Steven Zeliadt of the University of Washington advocated for greater use of so-called active surveillance. This approach “balances the desire to avoid treatment complications against the equally strong desire not to ignore a cancer—while at the same time minimizing the risk of overtreatment,” they explained.