Tumour markers in prostate cancer: The post-prostate-specific antigen era

Although prostate-specific antigen-based prostate cancer screening had a positive impact in reducing prostate cancer mortality, it also led to overdiagnosis, overtreatment and a significant number of unnecessary biopsies. In the post-prostate-specific antigen era, new biomarkers have emerged that can complement the information given by prostate-specific antigen, towards a better cancer diagnostic specificity, and also allowing a better estimate of the aggressiveness of the disease and its clinical outcome. That means those markers have the potential to assist the clinician in the decision-making processes, such as whether or not to perform a biopsy, and to make the best treatment choice among the new therapeutic options available, including active surveillance in lower risk disease. In this article, we will review several of those more recent diagnostic markers (4Kscore®, [-2]proPSA and Prostate Health Index, SelectMDx®, ConfirmMDx®, Progensa® Prostate Cancer Antigen 3, Mi-Prostate Score, ExoDx™ Prostate Test, the Stockholm3 test and ERSPC risk calculators) and prognostic markers (OncotypeDX® Genomic Prostate Score, Prolaris®, Decipher® and ProMark®). We will also address some new liquid biopsy approaches - circulating tumour cells and cell-free DNA - with a potential role in metastatic castration-resistant prostate cancer and will briefly give some future perspectives, mostly outlooking epigenetic markers.