cd57 as a routine neuroendocrine marker for liver metastasis background the characterization of hepatic metastases as having neuroendocrine origins is essential and the main markers currently used are chromogranin a cga and synaptophysin syn however these markers may exhibit certain limitations and the use of cd56 and cd57 can also be considered although due to low specificity their use is discouragedaim this study sought to compare the immunohistochemical expression of these markers in hepatic metastases of neuroendocrine neoplasms nenmaterials and methods eighteen samples were used for immunohistochemical staining with cga syn cd56 and cd57 antibodies the immunostaining reactions were compared according to its intensity i the percentage of labeled cells p and a final score i p statistical agreement between the markers was also evaluatedresults cd57 was expressed in the highest number of cases and also showed the most intense expression cga showed the highest number of cases with more than 80 positively stained area 722 followed by cd57 611 the highest average score i p was obtained for cd57 91 41 the best indices of agreement were between cga and cd57 with respect to positivity p 0021 and score p 0014 according to the primary site stomachduodenum lungs and undetermined subgroups showed the highest average scores for cd57 followed by cga for the small bowel subgroup the highest average score was obtained for cga followed by cd57conclusion our results highlight the importance of cd57 in the evaluation of hepatic metastases of nen and indicate that this marker should be included with cga and syn in routine diagnostic panels