Role of tumor thromboplastin in the mode of distribution of metastatic foci in the lung.

Crude tumor cell extract from rat ascites hepatoma AH130 revealed a high thromboplastic activity. Intravenous injection of the extract caused widespread thrombus formation in the capillaries, arterioles, and arteries of the lung. Intravenous inoculation of AH130 after an injection of the tumor cell extract produced metastatic foci in the larger arteries, compared with the case injected with only AH130 which developed metastatic foci mainly in and around the alveolar septa. These results suggest the role of tumor thromboplastin material in the mode of distribution of metastatic foci in the lung.