Pathological and IHC analyses using markers as Syn, neuron-specific enolase (NSE), and CHG-A are necessary for the diagnosis of GB-NEN.[7] The positive rates for Syn, EMA, and CD56 are relatively low.[15] Our case demonstrated positivity for CK, Syn, CgA, and CD56, thereby confirming the diagnosis of a gallbladder neuroendocrine tumor. Here, MUC1 is linked to neuroendocrine neoplasm.