Development of an ELISA for sPSP94 and utility of the sPSP94/sPSA ratio as a diagnostic indicator to differentiate between benign prostatic hyperplasia and prostate cancer

摘要

Background: The serum PSA (sPSA) test has low specificity for prostate cancer (PCa), since sPSA also rises in benign prostatic hyperplasia (BPH). Serum PSP94 (sPSP94), a major secreted prostate protein, is indicated as a PCa marker. The potential of SPSP94 and sPSA in conjunction with each other to improve specificity of diagnostic test for PCa needs to be evaluated.Methods: PCa patients (n = 33), BPH patients (n = 44) and healthy controls (n = 50) were recruited. A serum-based sandwich ELISA was developed to measure sPSP94 concentrations. Utility of sPSP94 in improving specificity of sPSA test was evaluated by studying sPSP94/sPSA ratios of study participants.Results: Considerable decrease in overlap among sPSP94/sPSA ratio values of BPH and PCa patients was observed, as compared to sPSP94 or sPSA alone. For differentiating between BPH and PCa patients, this ratio had a maximum area under the curve (AUC) of 0.859 (P = 0.0132) and had a comparable sensitivity (90.91%) to sPSA with an increased specificity of 70.45%. Further, decision curve analysis (DCA) showed that sPSP94/sPSA ratio had a superior net benefit in identifying PCa, in patients opting for biopsy.Conclusion: The sPSP94/sPSA ratio can be a better differentiating marker between BPH and PCa, than sPSP94 or sPSA alone.