Significance of plasma fibrinopeptide A (fpA) in patients with malignancy.

In 124 patients with various types of malignancy, fpA and delta fpA were measured. In 35 of these patients the effect of heparin injection on fpA and delta fpA was studied. All patients were ambulant without clinical signs of venous thromboembolism or DIC and had not received cytostatic, anticoagulant, or radiotherapy recently. In about 75% of these patients, fpA was elevated, whereas in the blood of one third of the patients, both elevated fpA levels and accelerated delta fpA were detected. Eight of the 45 patients with accelerated delta fpA (and elevated fpA) presented laboratory signs of low-grade DIC. In the patients taken at random for heparin administration, delta fpA normalized upon heparin injection, whereas in the majority of patients, irrespective of the fpA-generation rate, fpA levels were not affected by "adequate" heparinization. These results indicate that (1) about 30% of the (selected) patients admitted to our cancer clinic present with evidence of intravascular thrombin activity and (2) in 70% of these patients fpA is generated, at least in part, at a site not accessible to heparin. In addition 95% of patients with active metastatic disease showed an elevated fpA, whereas 90% of cancer patients in remission and 80% of patients without metastasis had a normal fpA, indicating that fpA can potentially be used to estimate the spread and the activity of the malignant process.