RESUMEN
Colorectal cancer is the third most often cause of morbidity and mortality due to cancer in Poland. Thromboembolic complications are common events during the course of the disease. It is well known that hemostatic proteins play an important role in cancer progression. The purpose of the study was to evaluate the in loco interactions among colorecatal cancer and coagulation factors. 21 cases of G2 colorectal adenocarcinoma obtained during surgical resection were examined. Immunohistochemical procedures according to ABC method were employed. Tissue factor (TF) and coagulation factors II, VII, X, IX were observed in cancer cells and except factors II and IX--in tumor associated macrophages. TF was also demonstrated in endothelial cells of small blood vessels. Strong expression of fibrinogen was observed among connective tissue at some distance around malignant tumor while weaker expression was found in tumor stroma. Expression of F(1+2), the by-product of thrombin generation, was revealed in cancer cells, macrophages and in the tumor stroma. The results indicate extravascular activation of blood coagulation in loco in colorectal cancer that is TF-dependent.