Diagnostic accuracy of prostate-specific antigen below 4 ng/mL as a cutoff for diagnosing prostate cancer in a hospital setting: A systematic review and meta-analysis

Purpose: A prostate-specific antigen (PSA) cutoff of 4 ng/mL has been widely used for prostate cancer screening in population -based settings. However, the accuracy of PSA below 4 ng/mL as a cutoff for diagnosing prostate cancer in a hospital setting is in-conclusive. We systematically reviewed the accuracy of PSA below 4 ng/mL cutoff in a hospital setting. Materials and Methods: We systematically reviewed the literature by searching major databases until March 2020, and a meta -analysis and quality assessment were performed. Results: A total of 11 studies were included at the completion of the screening process. The meta-analysis showed a sensitivity of 0.92 and a specificity of 0.16 for a PSA cutoff below 4 ng/mL. The area under the hierarchical summary receiver operating charac-teristic curve was 0.87, the positive likelihood ratio was 1.23, the negative likelihood ratio was 0.46, and the diagnostic odds ratio was 2.64. PSA sensitivities and specificities varied according to the cutoff range: 0.94 and 0.17 for 2 to 2.99 ng/mL, and 0.92 and 0.16 for 3 to 3.99 ng/mL, respectively. No significant differences in the sensitivity and specificity of PSA cutoffs in the range of 2 to 2.99 ng/mL and 3 to 3.99 ng/mL were found. Conclusions: Although a PSA cutoff <3 ng/mL is relatively more sensitive and specific than PSA >= 3 ng/mL, no significant differ-ences in sensitivity and specificity were found in the diagnosis of prostate cancer. Therefore, clinicians should choose an appropri-ate PSA cutoff on the basis of clinical circumstances and patients' characteristics.