Fibrinolytic activity of carcinoma of the colorectum

Twenty patients with carcinoma, mostly of the colorectum, and five without malignant tumors who were used as controls, have been investigated to elucidate the relationship between tumor fibrinolytic activity and the release of circulating malignant cells. The nature of the tumor fibrinolytic activity has been considered. The most significant fibrinolytic activity was seen in blood draining from the tumors and was evident in 80 per cent. Circulating malignant cells were recovered from half the patients, and in those with significant blood fibrinolysis, recovery from the draining vein reached 89 per cent. The most undifferentiated tumors appeared to be more active and released more cells. Fibrinolytic activity of tumor tissue derives from inflammatory cells, dead tumor cells, avascular areas of the tumor and vascular endothelium and is probably proteolytic as well as purely fibrinolytic.