Reduced levels of screening for prostate cancer using prostate-specific antigen (PSA) testing correspond with recent increases in the diagnosis of metastatic disease in the United States, according to a study that will be presented by Vidit Sharma, MD, and colleagues at the 2021 Genitourinary Cancers Symposium, taking place virtually February 11 to 13 (Abstract 228).
Vidit Sharma, MD
Study Details
Investigators obtained age-adjusted incidences of metastatic prostate cancer at diagnosis (per 100,000 men) from the North American Association of Central Cancer Registries from 2002 to 2016 for each U.S. state. They also obtained PSA screening estimates for each state from the Behavioral Risk Factor Surveillance System. The system collects this information for men at least 40 years of age every 2 years starting in 2002. The authors then correlated the incidence of metastatic prostate cancer to the proportion of men receiving PSA screening per state.
Key Findings
In the United States, the average percentage of men aged 40 or older screened for prostate cancer using PSA decreased from 61.8% in 2008 to 50.5% in 2016. At the same time, the average number of men diagnosed with metastatic prostate cancer (after adjusting for age) increased from 6.4 to 9 per 100,000 men.
KEY POINTS
- In the United States, the average percentage of men aged 40 or older screened for prostate cancer using PSA decreased from 61.8% in 2008 to 50.5% in 2016.
- At the same time, the average number of men diagnosed with metastatic prostate cancer (after adjusting for age) increased from 6.4 to 9 per 100,000 men.
- There was significant variation between states in terms of the percentage of men older than 40 who reported ever receiving PSA screening (40.1%–70.3%) and in the incidence of metastatic prostate cancer at diagnosis after adjusting for age (range = 3.3–14.3 per 100,000 men).
There was significant variation between states in terms of the percentage of men older than 40 who reported ever receiving PSA screening (40.1%–70.3%) and in the incidence of metastatic prostate cancer at diagnosis after adjusting for age (range = 3.3–14.3 per 100,000 men). However, statistical modeling demonstrated that reductions over time in PSA screening were associated with increased metastatic prostate cancer diagnoses, and states with larger reductions in PSA screening tended to have larger increases in metastatic prostate cancer diagnoses.
“The variation between states is one of the precise strengths of our study. The magnitude of decreased PSA screening was correlated to the magnitude of increased metastatic disease, suggesting that there may be a link at population level,” said lead author Dr. Sharma, health services fellow in urologic oncology at the University of California, Los Angeles.
One set of guidelines, published by the U.S. Preventive Services Task Force (USPSTF)—an independent, volunteer group of national experts in prevention and evidence-based medicine—did not recommend PSA screening regardless of age in its 2008 and 2012 guidelines. However, these were updated in 2018 to recommend that “men aged 55 to 69 years make an individual decision about whether to be screened after a conversation with their clinician about the potential benefits and harms.” The task force recommended against PSA screening in men over 70.
“This study suggests that reduced PSA screening may come at the cost of more men presenting with metastatic prostate cancer. Patients should discuss the risks and benefits associated with PSA screening with their doctor to identify the best approach for them,” said Robert Dreicer, MD, MS, MACP, FASCO, ASCO expert in genitourinary cancers.
Next Steps
The investigators plan to look for correlation between decreased screening and mortality, as well as investigating the effects of other factors.
Disclosure: Dr. Sharma was supported by the VA Health Services Research & Development Fellowship. For full disclosures of the study authors, visit coi.asco.org.