Prostate Cancer Mortality in Men Aged 70 Years Who Recently Underwent Prostate-Specific Antigen Screening.

IMPORTANCE

Continuing prostate-specific antigen (PSA) screening after age 70 years might benefit men at high risk of prostate cancer-specific mortality (PCSM) or metastatic prostate cancer (mPCa), but the relative value of clinical factors (race and ethnicity, competing mortality, and PSA history) in identifying men at higher vs lower risk is unknown.

OBJECTIVE

To examine the value of PSA levels, race and ethnicity, and competing mortality in risk stratification for PCSM and mPCa in men after age 70 years.

DESIGN, SETTING, AND PARTICIPANTS: In this cohort study, clinical data of all men receiving health care through the Veterans Health Administration who turned age 70 years between 2008 and 2020 and had a normal screening PSA value between age 65 and 69 years (<4 ng/mL [baseline PSA]) and no prior history of prostate cancer or biopsy were examined. The data cutoff date was December 26, 2023.

EXPOSURE

The most recent screening PSA value from age 65 to 69 years, self-reported race and ethnicity, and competing mortality risk derived from a machine learning model.

MAIN OUTCOME AND MEASURES

The 10-year absolute risk of PCSM and mPCa were determined using regression modeling.

RESULTS

The cohort included 921 609 men who turned 70 years between 2008 and 2020; 11% of whom self-reported as Black and 82% as White race. Between age 65 and 70 years, 45% of patients had a baseline PSA of less than 1.00 ng/mL, and 32% had a baseline PSA of 1.00 to 1.99 ng/mL. Most patients (87%) continued to undergo screening past age 70 years, with little variation by competing mortality risk or race and ethnicity. The 10-year cumulative incidence of PCSM was 0.26% overall, and 95% of men had a 10-year risk less than 0.73%. Higher baseline PSA level between age 65 and 69 years was associated with 10-year PCSM risk (0.79% for 3.00-3.99 ng/mL vs 0.10% for 0.20-0.99 ng/mL), race and ethnicity (0.36% for Black vs 0.25% for White), and competing mortality (0.24% for the highest quintile vs 0.21% for the lowest quintile). Similar results were found for mPCa. Low PSA (0.20-0.99 ng/mL) was associated with very low PCSM and mPCa risk, even among Black men in the healthiest quintile of competing mortality risk (10-year PCSM risk, 0.08% [95% CI, 0.01%-0.44%]; 10-year mPCa risk 0.24% [95% CI, 0.10%-0.52%]).

CONCLUSIONS AND RELEVANCE

In this cohort study, the findings suggest that most men receiving care through the VHA continue PSA screening after age 70 years despite low absolute 10-year PCSM risks. The PSA values from age 65 to 69 years may be highly informative for adverse prostate cancer outcomes after age 70 years, with a PSA less than 1 ng/mL associated with a very low risk of long-term PCSM and mPCa.