Fibrinopeptide A (FPA) level and fibrinogen kinetics in patients with malignant disease.

FPA level, fibrinogen turnover rate, and fibrinolytic activity were studied on 18 patients with malignant disease. It was found that the FPA levels were significantly elevated and were correlated with fibrinogen turnover rate (r = 0.74, p less than 0.001) and FDP (r - 0.58, p less than 0.02). Estimated FPA turnover rate was also correlated with fibrinogen turnover rate (r = 0.70, p less than 0.001). These results suggest that fibrinogen catabolism in patients with malignant disease is related with thrombin proteolysis. However, ratios of 1/2 FPA turnover rate to fibrinogen turnover rate suggest that intravascular thrombin proteolysis is not the major determinant of fibrinogen catabolism. It is suspected that extravascular thrombin proteolysis is responsible for the elevation of plasma FPA level which is correlated with acceleration of fibrinogen catabolism.