The Science


There is a delicate balance between blood clotting (coagulation) and clot-dissolving (fibrinolysis) in non-cancer patients.

In cancer patients, that balance is disturbed by molecules released from tumours, including Urokinase Plasminogen Activator (u-PA) and Tissue Factor (TF). Both of these molecules activate enzymes that transform Fibrinogen, which is the major clotting protein in humans.


In addition, cancer cells release proteins that cut the products created by both of these pathways.

The cancer-activated protease enzymes, Plasmin and Thrombin respectively, dramatically increase the amount of Fibrin Degradation Products (FDP’s) in cancer patients relative to non-cancer patients.

Therefore, FDP’s are over produced in cancer patients because cancer cells release the activators for the proteolytic enzymes that cleave Fibrin and Fibrinogen to form FDP.

CST’s Cancer test selectively measures FDP’s (such as the unique epitopes resulting from the proteolytic degradation of Fibrinogen), formed outside cancer cells in the extracellular matrix and extracellular milieu. These epitopes are not present in the native fibrinogen molecule.

As described above, the concurrent formation of Fibrin by plasminogen activators found in high levels in malignant cells and the secretion of proteases (some of which act on the proteins of the coagulation cascade in malignant conditions), cause a resultant increase in the amount of FDP’s in cancer patients.

The extent of proteolytic degradation can be correlated with theactivity of tumour cells and used indirectly to evaluate their tumour burden or degree of malignancy.

CST’s Tumour Markers measure the increased protease activity around growing tumours and their release of FDP’s at a higher rate into the interstitial fluid by cancer cells compared to normal cells.

In summary, CST’s Cancer Test detects the breakdown products that result from the disregulation of clot-forming or clot-dissolving processes in cancer patients, effectively qualifying and quantifying the amount of tumour marker present.