TP53 and neuroendocrine carcinoma: MANECs can be divided into 3 subtypes such as composite, collision, and amphicrine tumors.[13] Immunohistochemically, p53 was ubiquitously positive in both components, whereas the expression of chromogranin A, synaptophysin and NSE, neuroendocrine markers, was limited to the NEC component, indicating a composite tumor on the basis of microscopic findings.