Genomic characterization of treatment-associated small cell neuroendocrine carcinoma of the prostate

Genomic characterization of treatment-associated small cell neuroendocrine carcinoma of the Abstract Treatment-associated small cell neuroendocrine carcinoma of the prostate (t-SCNC) is an aggressive prostate cancer variant with rising incidence. Although morphologically similar to de novo small cell prostate cancer, t-SCNC is thought to emerge from metastatic castration-resistant prostate cancer (mCRPC) under the selective pressure of prolonged AR-targeted therapies. t-SCNC is associated with a distinct transcriptional landscape, characterized by the upregulation of stem cell-associated and neuronal programs (e.g., SOX2, N-MYC, FOXA2) and decreased canonical AR signaling. In addition, as with other neuroendocrine carcinomas, RB1 loss and inactivating TP53 mutations are key genomic hallmarks of t-SCNC. Nevertheless, despite their histologic, molecular, and clinical differences, there is a striking degree of genomic overlap between t-SCNC and its adenocarcinoma counterpart. This finding underscores the clonal evolution of t-SCNC from mCRPC, as well as the importance of epigenetic mechanisms in regulating tumor phenotype. In this review, we summarize the key genomic, transcriptional, and epigenetic features of t-SCNC and discuss how recent advances in our understanding of molecular drivers of t-SCNC have contributed to improving the diagnosis and treatment of this aggressive disease.