Systematic Review: FGF-23 in Prostate Cancer Diagnosis and Comparison With Other Biomarkers

Background: Prostate cancer represents a major health burden in sub-Saharan Africa, where patients often present with aggressive disease and rising incidence rates. This review evaluates the diagnostic and prognostic performance of Fibroblast Growth Factor 23 (FGF-23) relative to the clinical standards, Prostate-Specific Antigen (PSA) and Alpha-methylacyl-CoA racemase (AMACR), to determine its utility in enhancing diagnostic precision. Methods: A systematic literature review was conducted across studies published between 2010 and 2025. The analysis focused on the sensitivity, specificity, and Area Under the Curve (AUC) of FGF-23, PSA, and AMACR, with a specific emphasis on data from African cohorts and skeletal-related outcomes. Results: FGF-23 demonstrated a diagnostic sensitivity of approximately 66.7% and a superior specificity of 83.3% in differentiating prostate cancer from benign prostatic hyperplasia (BPH). While PSA maintained a higher overall sensitivity (85.0% to 90.0%), its specificity was significantly lower (25.0% to 45.0%), leading to high false-positive rates in the gray zone (4 to 10 ng/mL). AMACR showed high specificity in tissue-based studies (90.0% to 95.0%) but lower utility in serum screening. Diagnostic accuracy for FGF-23 ranged from an AUC of 0.69 to 0.75, consistently outperforming PSA in the gray zone. Furthermore, FGF-23 was identified as a high-value prognostic marker for bone metastasis and skeletal-related events, correlating strongly with tumor invasiveness and poor survival. Conclusion: FGF-23 serves as a potent adjunct biomarker that addresses the specificity limitations of PSA testing. Its dual role as a diagnostic filter for BPH and a prognostic indicator for metastatic spread makes it particularly relevant for African populations. Further large-scale prospective validation is recommended to standardize FGF-23 integration into multi-marker diagnostic protocols.