Prostate cancer antigen 3 moderately improves diagnostic accuracy in Chinese patients undergoing first prostate biopsy

Prostate cancer antigen 3 （PCA3） is a biomarker for diagnosing prostate cancer （PCa） identified in the Caucasian population. We evaluated the effectiveness of urinary PCA3 in predicting the biopsy result in 500 men undergoing initial prostate biopsy. The predictive power of the PCA3 score was evaluated by the area under receiver operating characteristic （ROC） curve （AUC） and by decision curve analysis. PCA3 score sufficed to discriminate positive from negative prostate biopsy results but was not correlated with the aggressiveness of PCa. The ROC analysis showed a higher AUC for the PCA3 score than %fPSA （0.750 vs 0.622, P = 0.046） in patients with a PSA of 4.0-10.0 ng ml-I, but the PCA3-based model is not significantly better than the base model. Decision curve analysis indicates the PCA3-based model was superior to the base model with a higher net benefit for almost all threshold probabilities, especially the threshold probabilities of 25%-40% in patients with a PSA of 4.0-10.0 ng ml-1. However, the AUC of the PCA3 score （0.712） is not superior to %fPSA （0.698） or PSAD （0.773） in patients with a PSA 〉10.0 ng ml-1. Our results confirmed that the RT-PCR-based PCA3 test moderately improved diagnostic accuracy in Chinese patients undergoing first prostate biopsy with a PSA of 4.0-10.0 ng ml-1.

Prostate cancer antigen 3 test for prostate biopsy decision： a systematic review and meta analysis

Background The specificity for early interventions of prostate-specific antigen （PSA） in prostate cancer （PCa） is not satisfactory.It is likely that prostate cancer antigen 3 （PCA3） can be used to predict biopsy outcomes more accurately than PSA for the early detection of PCa.We systematically reviewed literatures and subsequently performed a meta-analysis.Methods A bibliographic search in the database of Embase,Medline,Web of Science,NCBI,PubMed,CNKI,and those of health technology assessment agencies published before April 2013 was conducted.The key words used were ＂prostatic neoplasms＂,＂prostate＂,＂‘prostate,＇ ‘carcinoma＇ or ‘cancer＇ or ‘tumor＇,or ‘PCa,＇＂ and free terms of ＂upm3＂,＂pca3＂,＂dd3＂,＂aptimapca 3＂,and ＂prostate cancer antigen 3＂.All patients were adults.The intervention was detecting PCA3 in urine samples for PCa diagnosis.We checked the quality based on the QUADAS criteria,collected data,and developed a meta-analysis to synthesize results.Twenty-four studies of diagnostic tests with moderate to high quality were selected.Results The sensitivity was between 46.9％ and 82.3％; specificity was from 55％ to 92％; positive predictive value had a range of 39.0％-86.0％; and the negative predictive value was 61.0％-89.7％.The meta-analysis has heterogeneity between studies.The global sensitivity value was 0.82 （95％ Cl 0.72-0.90）; specificity was 0.962 （95％ Cl 0.73-0.99）; positive likelihood ratio was 2.39 （95％ Cl 2.10-2.71）; negative likelihood ratio was 0.51 （95％ Cl 0.46-0.86）; diagnostic odds ratio was 4.89 （95％ Cl 3.94-6.06）; and AUC in SROC curve was 0.744 1.Conclusion PCA3 can be used for early diagnosis of PCa and to avoid unnecessary biopsies.

PCA3 and TMPRSS2-ERG gene fusions as diagnostic biomarkers for prostate cancer

The incidence of prostate cancer （PCa） is rising steadily among males in many countries. Serum prostate-specific antigen （PSA） is widely applied to clinical diagnosis and screening of PCa. However, the so-called grey area of PSA levels 4.0-10.0 ng/mL has a low specificity of 25-40% resulting in a high rate of negative biopsy and overtreatment. So in order to treat PCa patients in early stage, there is an urgent need for new biomarkers in PCa diagnosis. The PCA3 gene, a non-coding RNA （ncRNA） that is highly expressed in prostate cancer （PCa） cells, has been identified as a molecular biomarkers to detect PCa, of which PCA3 has already under clinical application. PCA3 is strongly overexpressed in malignant prostate tissue compared to benign or normal adjacent one. Newly, PCA3 is considered to be a promising biomarker in clinical diagnosis and targeted therapy. The diagnostic significance of PCA3, however, is awaiting further researches. Moreover, it has been demonstrated recently that TMPRSS2-ERG gene fusion is identified as the predominant genetic change in patients diagnosed with PCa. Recent study revealed that combination of the PC43 and TMPRSS2-ERG gene fusion test optimizes PCa detection compared with that of single biomarker, which would lead to a considerable reduction of the number of prostate biopsies. In this review, we focused on the potential use of PCA3 and TMPRSS2-ERG gene fusion detection in the diagnosis of PCa.