[Circulating tumor cells and advanced prostate cancer]

Despite development and widespread of PSA, current tools evaluating prostate cancer still give inconsistent or insufficiently relevant results. As encouraging data raised from circulating tumor cells detection in colon or breast cancer, they were evaluated as a surrogate prostate cancer biomarker. Tumor cells need to leave their surrounding primary environment and to survive in mesenchymal environment before they spill and metastasize. Basic research revealed several mutations required through a complex transition phenomenon, including dormancy steps. Circulating cells detection techniques are based on molecular and immunologic methods. Most of them need an enrichment step to improve sensibility and/or specificity. As of today, Veridex' CellSearch is the only FDA approved technique in the evaluation of castration resistant prostate cancer response to new drugs. Clinical research using other techniques highlighted the need for clinical endpoints, as there's no relevant tool and as techniques' target differ. Further studies are required to improve circulating tumors cells' staging and prognosis value. Cellular characterization may be the way to identify metastasis development potential more than the spillage burden. Those techniques still need improvements before they are included in daily practice decisional trees.