An Unusual Type of Spiculated Erythrocyte in Metastatic Liver Disease and Hemolytic Anemia

A patient had hemolytic anemia associated with spiculated erythrocytes and massive hepatic metastases from rectal carcinoid. The patient's erythrocytes resembled acanthocytes found in abetalipoproteinemia when examined by scanning electron microscopy. The patient's erythrocytes contained normal quantities of cholesterol, and his serum did not transform normal erythrocytes into spiculated cells in vitro. Normal erythrocytes infused into the patient did not acquire the filtration properties of acanthocytes, yet their survival was shortened, suggesting that the mechanism of hemolysis was independent of acanthocyte formation. These findings are discussed in relation to the acanthocytes found in other liver diseases. The great variability in results obtained studying the mechanism of acanthocyte formation suggest that multiple factors may lead to their formation.