Emerging tools for the early detection of prostate cancer.

Introduction: Prostate cancer (PCa) is the second most common cancer in men globally, with a rising incidence. Early detection through population-based screening by Prostate Specific Antigen (PSA) testing improves survival outcomes, at the expense of overdiagnosis and overtreatment of clinically insignificant disease. Here, we explore emerging tools for more effective PCa early detection and evaluate their potential roles for PCa screening. Materials and Methods: Key articles on emerging adjuncts and alternatives to PSA for PCa early detection were identified. Results: Multiparametric MRI (mpMRI) remains the gold standard modality for identifying clinically significant PCa and has been evaluated for screening. Newer imaging strategies incorporating biparametric MRI (bpMRI) or multiparametric ultrasound (mpUS) potentially offer similar accuracy to mpMRI. Saliva-derived polygenic risk scores (PRS) hold potential as a non-invasive screening tool to identify at-risk patient groups. Blood-based biomarker tests can improve risk stratification, reducing unnecessary biopsies while maintaining detection of clinically significant cancers compared to PSA alone. Urine-based biomarker tests have been examined for the early detection and risk stratification of clinically significant disease as adjuncts to PSA testing. Conclusion: PSA is commonly used to detect early PCa, but its lack of specificity and associated overdiagnosis risk has led to controversy over its use for population-based screening. Imaging modalities such as mpMRI have reduced detection of clinically insignificant PCa, and emerging cost-effective alternatives, such as bpMRI and mpUS, show promise. Molecular biomarkers and PRS for risk stratification may help target imaging-based early detection more effectively to at-risk populations. Prospective randomised clinical trials are urgently needed to evaluate the performance of different modalities for population-wide screening. Future developments may involve technologies such as artificial intelligence and diagnostic tests that incorporate circulating tumour markers.