The effect of hyperlipemia on pulmonary metastases of Walker 256 carcinosarcoma in the rat.

Rats made hyperlipemic by feeding a high fat diet for ~1 days showed increased inhibition of fibrinolysis. Tumor cells injected into these hyperlipemic animals were removed from the circulation rapidly as determined by direct cell counts and subcutaneous injection of blood into weanling animals. Metastases in the lungs occurred much more frequently in hyperlipemic than control animals. This occurred with 100,000 cells/animal, but the results were not significant. With ~5,000 cells/animal a significant increase in pulmonary metastases was noted. This increase in pulmonary metastases was seen in the animals that died before 9 weeks and in those that were sacrificed after surviving 9 weeks. Not only was the number of animals with metastases greater, but larger numbers of metastases were seen in the lungs of the individual hyperlipemic animals.