[Aggressive variants of castration resistant prostate cancer (CRPC): neuroendocrine prostate cancer.]

Castration resistant prostate cancer (CRPC) is characterized by an important molecular, pathological and clinical heterogeneity. Although most of them present androgen receptor (AR) signal dependence, there are independent phenotypes. Neuroendocrine prostate cancer (NEPC) is a rare histologic subtype with adverse prognosis due to late diagnosis, heterogeneous clinical features and lack of effective systemic treatments. Platinum based chemotherapy is the standard treatment, presenting short limited responses. There are pure forms or mixed with adenocarcinoma component. De novo diagnosis is unusual, being more frequent in advanced stages of prostate cancer, as a consequence of the inhibition of androgen receptor performed by various treatments. Thus, it could represent an aggressive evolution from carcinoma through a NEEpithelial transdifferentiation. Development of preclinical studies has permitted characterization of molecular and genomic alterations associated with this evolution and they may help to develop new therapeutic targets. Over the last years, there have been important advances in identification and characterization of clinical and pathological CRPC variants. NEPC is one of the most aggressive subtypes. A better knowledge of the disease biology is necessary to develop new treatments and biomarkers that help to manage this aggressive variant of PC.