PSA Levels and Mortality in Prostate Cancer Patients.

ABSTRACT

INTRODUCTION: Prostate cancer (PC) is the second most common cancer among men around the world. Several smaller studies have explored the relationship between elevated PSA and mortality, but results have been conflicting. Additionally, studies have shown that Black men are more likely to be diagnosed with PC at late-stages and may have a twofold increase in mortality risk. This study aims to evaluate the relationship between PSA levels and mortality in patients with PC and differences between Black versus White patients. METHODS: In this retrospective study, the TriNetX database, was used to extract de-identified EMRs of 198,083 patients. Patients were included if they were diagnosed with PC and had obtained a PSA level (measured in ng/mL) within 6 months prior to diagnosis. Cohorts were separated into 7 groups based on intervals of PSA, ranging from < 2 to ≥ 500 and compared to a control cohort with a PSA of 4 to 20 for differing 2-year mortality rates. A subgroup analysis was performed to compare mortality differences between Black and White patients. A posthoc analysis evaluated 5- and 10-year mortality amongst all patients with PC. RESULTS: After propensity matching, mortality risk was significantly lower for patients with PSA < 2 (5.9% vs. 7.5%; RR 0.784; P < .001) when compared to the control cohort. Mortality was significantly higher for all other subsequent PSA intervals > 20, with the lowest risk ratios at PSA 20-100 (24.1% vs. 10.0%; RR 2.419; P < .001) and highest at PSA 200 to 500 (50.4% vs. 10.8%; RR 4.673; P < .001). The sub-group analysis showed that when compared to White patients, Black patients with PSA < 20 had similar mortalities, but had significantly lower 2-year mortality rates at PSA levels ≥ 20. The posthoc analysis of PSA levels and 5- and 10-year mortality of all patients with PC showed similar trends to the 2-year outcomes. CONCLUSION: This study found that prostate cancer patients with significantly elevated PSA levels have a greater mortality, and Black patients have lower 2-year mortality rates than their White counterparts when matched for PSA levels greater than 20.