Figure 1: (a and b) Liver biopsy showing that liver tissue is infiltrated by solid nests of atypical cells. The cells are medium to large, have pleomorphic, hyperchromatic nuclei, high nuclear-to-cytoplasmic ratio, and abundant atypical mitotic figures. Cytoplasm is eosinophilic to amphophilic color with finely cytoplasmic granules are identified. Nuclei are central, round-to-oval, with loss of “salt-and-pepper” chromatin. (c and d) Immunohistochemistry showing that atypical cells are positive with CKAE1/AE3, synaptophysin, and CD56. They are negative with chromogranin and TTF1. Ki-67 proliferative index is 40%. These findings diagnose neuroendocrine tumor WHO grade 3. However, it is unclear whether this represents a possible metastatic neuroendocrine tumor or represents a primary liver neuroendocrine neoplasm