SYP and neoplasm: This may be attributed to several factors: The lack of specific biomarkers [e.g., NE markers such as synaptophysin (SYP), neuron-specific enolase (NSE), chromogranin A (CgA), and neural cell adhesion molecule (CD56)] hinders early detection, diagnosis, and intervention [35–37]; limited therapeutic options with innate or acquired resistance further constrain clinical management [38]; and the immunologically cold tumor microenvironment (TME) characteristic of NEPC substantially compromises immunotherapy efficacy [39].