Aiming for the Middle Ground on PSA Testing
In the midst of the debate over PSA testing, the new National Comprehensive Cancer Network (NCCN) Guidelines for Prostate Cancer Early Detection aim to maximize the benefits and minimize the harms of PSA testing. These guidelines are important because many health insurance companies determine coverage based on NCCN panel recommendations.
Previously, the NCCN guidelines recommended active surveillance instead of treatment in early-stage and low-risk prostate cancer. The updated guidelines for early detection are linked to the NCCN guidelines for prostate cancer treatment, which should translate into less overtreatment.
Baseline Testing, Stratifying Risk
The NCCN guidelines recommend that men obtain a PSA test at age 45 years. This PSA test value would determine the frequency of subsequent testing. The NCCN suggests annual to biannual follow-up PSA testing for men with a PSA above the median for their age, and men with a PSA below the median should have another PSA test at age 50. Median PSA levels are 0.7 ng/mL for men 40-49 years of age and 0.9 ng/mL for men 50-59 years.
This recommendation is based on observational data suggesting that baseline PSA testing men in their 40s and early 50s might enable future risk stratification for prostate cancer. A large study of Swedish men demonstrated that a single PSA test before age 50 predicted the risk for subsequent prostate cancer diagnosis, metastases and death up to 30 years later.
Other recommendations include advising men with a PSA above 1.0 ng/mL to have a follow-up PSA test annually or biannually, and that men should generally be referred for a biopsy when their PSA is higher than 3 ng/mL.
A large trial from Sweden showed a 44% lower death rate in men who underwent regular prostate cancer screening. Nine years after screening was stopped at upper age limit of 69, the incidence of high-risk and fatal prostate cancer increased steadily in the screening arm until it equaled that of the unscreened arm. This is level-1 evidence that restricting screening too soon and too much results in loss of benefits.
Emphasis on Life Expectancy
The NCCN recommends offering PSA testing only to men with a life expectancy of more than 10 years. For older men, the NCCN offers a number of ages at which to stop PSA testing. Screening can stop at age 69, continue up to age 74 with an increased PSA threshold for biopsies, or stop at age 75 for men with a PSA below 3.0 ng/mL.
In the U.S. the life expectancy is 15 years for a 70 year-old man and more than 10 years for a 76-year-old man. Men older than 70 are more likely to have aggressive prostate cancer.
Dr. Catalona is part of the NCCN prostate cancer early detection panel, which created the guidelines. The guidelines were presented at the NCCN 19th Annual Conference in March 2014 and were published in Journal of the National Comprehensive Cancer Network in April.