Hematological alterations in tumor-bearing rats, with reference to pathogenesis of chronic type of disseminated intravascular coagulation syndrome.

Hematological studied were carried out serially in the rats transplanted subcutaneously with Yoshida ascites hepatoma AH-109A. Significant changes were observed in fibrinogen level, fibrinogen degradation products, recalcification time, platelet count, and fragmentation of red blood cells. Formation of thrombi was revealed in the vessels of tumor tissue morphologically from early stage when the tumor grew to a palpable size. Thrombi were formed also in the arterioles of the lungs in the terminal stage. Bleeding tendency was noted in some cases at death. These findings suggested the experimental induction of a type of disseminated intravascular coagulation. The systemic changes of the blood occurring in the terminal stage were preceded by localized intravascular coagulation and fibrinolysis in the tumor in early stage of tumor growth.