A clinicopathologic study of primary hepatic carcinoid tumors

Six cases of primary hepatic carcinoid tumors were studied with combined immunocytochemical and electron microscopic techniques. Positive tumor immunostaining with PHE5, LK2H10, neuron‐specific enolase (NSE), serotonin, gastrin, and insulin antibodies was observed. At the ultrastructural level, cytoplasmic dense granules were seen in all the cases tested. This finding supports a putative origin of these carcinoids found in the liver from a pluripotential stem cell. The clinical course and follow‐up of these cases suggests that this unusual hepatic neoplasm has a more favorable prognosis than other forms of hepatic cancer.