Pseudocystic liver metastases in patients with carcinoid tumors: report of three cases.

Three of 30 patients (10%) with carcinoid tumors metastatic to the liver had large hepatic pseudocysts. One of the patients had an atypical carcinoid tumor that was markedly deficient in aromatic aminoacid decarboxylase and thus secreted 5-hydroxytryptophan as well as ACTH. Postmortem examination of this patient suggested that the mechanism of pseudocyst formation was probably infarction with liquefaction necrosis of tumor nodules. The authors' observations suggest that carcinoid tumors metastatic to the liver may not infrequently result in hepatic pseudocysts.