Estimated lifetime harms and benefits of continuing biennial prostate cancer screening in older men by comorbidity group

BACKGROUND: Prostate-specific antigen (PSA) screening prevents prostate cancer death but also leads to overdiagnosis-diagnosis that would not occur during a man's lifetime without screening-particularly in older men and those with life-limiting comorbidities. Modern screening approaches attempt to mitigate overdiagnosis in older men by using a higher PSA threshold for further evaluation using magnetic resonance imaging (MRI), and discontinuing screening in men with low PSA levels. However, long-term harms and benefits have not been estimated. METHODS: Two microsimulation models estimated lifetime harms and benefits of modern screening approaches in men who were screened biennially at ages 50-70 years, remained undiagnosed with prostate cancer at age 72 years, and faced varying risks of competing mortality based on previously estimated comorbidity-adjusted life tables. RESULTS: By using a PSA threshold of 6.5 ng/mL for evaluation with MRI and MRI-targeted biopsy, estimated ratios of overdiagnoses to cancer deaths prevented were similar when all men aged 70 years or older continued screening versus when only in men with PSA levels ≥ 3.0 ng/mL continued screening. For men with no comorbidities, this ratio increased from 2.7-3.1 at age 72 years to 4.5-5.1 at age 76 years. For men with severe comorbidities, this ratio increased from 9.6-10.2 at ages 72 to 11.3-12.6 at 76 years. CONCLUSIONS: Even using modern approaches, the ratio of overdiagnoses per cancer death prevented increases with age and is at least double in men with severe life-limiting comorbidities compared with age-matched men with no comorbidities. The current results can help inform patients and providers about when to stop PSA screening.