The diagnosis of prostate cancer is limited by low specificity and invasiveness. To address this, researchers developed a highly accurate, noninvasive reverse transcription-quantitative polymerase chain reaction (RT-qPCR)-based urinary PCA3 assay, exploring whether first-morning urine could replace the conventional post-digital rectal examination (DRE) sample.
Three prospective multicenter cohort studies were conducted on 643 Chinese men, quantifying urine PCA3 expression by RT-qPCR using either the novel reference gene microseminoprotein-beta (MSMB) or the conventional kallikrein-related peptidase 3 (KLK3, encoding prostate-specific antigen). Diagnostic performance was evaluated by receiver operating characteristic (ROC) analysis in Cohort I (n = 176) and validated in Cohort II (n = 350); in Cohort III (n = 117), diagnostic accuracy was compared between DRE and non-DRE urine samples.
The PCA3/MSMB system showed high precision and stability. In Cohort I it outperformed the PCA3/KLK3 test, with a higher AUC (0.869 vs. 0.830, p = 0.0468), higher sensitivity (82.1% vs. 79.0%), and higher specificity (77.8% vs. 74.1%); Cohort II confirmed these results (sensitivity 82.63%, specificity 77.50%). In Cohort III, diagnostic performance did not differ significantly between non-DRE and DRE samples (AUC 0.859 vs. 0.850, p = 0.6262). The authors conclude that the PCA3/MSMB urine test is a promising noninvasive diagnostic tool that can reduce unnecessary biopsies and improve detection accuracy using non-DRE urine samples.
The work titled “Novel reference gene microseminoprotein‐beta based prostate cancer antigen 3 urine test: Enhanced diagnostic performance for prostate cancer and feasibility of non‐digital rectal examination urine sampling” was published in UroPrecision (published on April 2, 2026).
doi:10.1002/uro2.70060