This work provides evidence that the production by monocytes of hepatocyte stimulating factor(s) for fibrinogen biosynthesis was dramatically increased when monocytes were exposed to Adriamycin. This effect was related to an increased production of leukaemia inhibiting factor (LIF), a cytokine known to stimulate fibrinogen biosynthesis by hepatic cells. Adriamycin also induces an increase in membrane-associated urokinase on monocytes. These results are consistent with the clinical observation in patients with ovarian cancer that when the CA-125 tumour marker decreases during chemotherapy, an increased level of D-dimer is a marker of good prognosis.