Characterization of murine hepatoma BW7756. III. Hematological profile of a tumor-associated anemia.

A severe anemia develops in recipient C57L/J mice after syngeneic transplantation of the BW7756 murine hepatoma. The tumor undergoes an exponential growth spurt in the 14-21 days post-implantation, accompanied by a parallel increase in serum alpha-fetoprotein levels and a significant decrease of hemoglobin concentration and hematocrit extending to the 28th day. Concomitant with the decreased hematocrit, the blood volume displayed a 10% increase. The blood cell population was generally one of reticulocytosis and leukocytosis. Mild icteric plasma was observed and both "cold" and "warm" antibodies were detected in the sera of tumor-bearing mice. An elevation of IgM was observed by day 7, followed by a depletion of IgG1 and IgG2 throughout the tumor growth period. When RBCs of tumor-bearing mice were compared to those of normal mice, the same degree of osmotic fragility was found. However, the lifespan of the transfused RBC was shorter in tumor-bearing mice than in normal mice (half-life: 2 days vs. 4 days). The data suggest a type of auto-immune hemolytic anemia which is analogous to various hematopoietic disturbances described for murine hosts bearing solid tumors distal to hematopoietic sites.