RESUMO
【Objective】 To evaluate the predictive value of isoform [-2] proprostate-specific antigen, p2 PSA (p2PSA) and its derived indexes for prostate cancer in a Chinese cohort with PSA 4-20 ng/mL. 【Methods】 A total of 139 males scheduled for biopsy were enrolled in the prospective study from Nov.2021 to Jun.2022. The total PSA (tPSA), free PSA (fPSA), fPSA/tPSA (f/t) and p2PSA were collected, and the percentage of p2PSA(%p2PSA) and prostate health index(PHI) were calculated. The predictive value of p2PSA and its derived indexes were compared with traditional indexes with receiver operating characteristic (ROC) curve and Logistic analysis. 【Results】 Prostate cancer was found in 54 cases (38.8%). There were significant statistical differences in tPSA(10.68 vs.8.14, P=0.021), f/t(0.13 vs.0.16, P=0.006), p2PSA(30.25 vs.19.81, P<0.001), %p2PSA(21.52 vs.13.15, P<0.001) and PHI(64.3vs.38.2, P<0.001) between prostate cancer patients and non-prostate cancer patients. The area under the ROC curve (AUC) of tPSA, fPSA, %fPSA, p2PSA, %p2PSA and PHI were 0.63, 0.51, 0.63, 0.71, 0.73, and 0.80, respectively. The inclusion of %p2PSA and PHI significantly increased the prediction efficiency of the basic prediction model (AUCbase+PHI=0.81, AUCbase+%p2PSA=0.78, AUCbase=0.67). With 35 as the recommended cut-off value of PHI, the incidence of meaningless puncture was reduced by 25.8%(36/139). 【Conclusion】 The application of p2PSA and its derived indexes have good predictive value for patients with PSA 4-20 ng/mL. The combined detection of %p2PSA and PHI can significantly increase the detection efficiency of prostate cancer and reduce the incidence of meaningless prostate puncture by 25.8%.