Blood rheology during chemotherapy in patients with ovarian cancer

The use of platinum based chemotherapy in ovarian malignancy and other cancer types is known to be associated with deep vein thrombosis. In a prospective study of 47 patients with ovarian cancer of International Federation of Gynecology and Obstetrics stage Ib-IV, serial rheological parameters were determined (plasma viscosity, red blood cell aggregation under conditions of stasis and low shear) in addition to hemoglobin, hematocrit, leukocytes, platelets, and fibrinogen. At the same time the incidence of deep vein thrombosis was recorded before, during six cycles of first line cisplatinum/epirubicin/cyclophosphamide chemotherapy, and 2 months thereafter (two-months check-up). Only six patients with previous deep vein thrombosis concomitantly received thrombosis prophylaxis once with 3000 anti Xa Units/day subcutaneously low molecular weight heparin (Certoparin, NOVARTIS) throughout chemotherapy. Before each cycle of chemotherapy impedance plethysmography was used for deep vein thrombosis screening and when this was suspected on the basis of physical examination or a pathological result of impedance plethysmography, ascending venography of both legs was performed. During chemotherapy, the venographically proven deep vein thrombosis incidence was 10.6%; (95% CI: 3.5-23.1) with no differences in occurrence between FIGO stages. Before operation mean plasma viscosity was higher in patients who developed deep vein thrombosis postoperatively (n = 5; 1.46 +/- 0.2 mPas) and during chemotherapy (n = 5; 1.49 +/- 0.1 mPas) as compared to those without deep vein thrombosis (1.38 +/- 0.2 mPas; p = 0.04). Postoperatively (before chemotherapy) none of the rheological variables were significantly different in patients with versus those without deep vein thrombosis during chemotherapy. Leukocyte and platelet counts decreased significantly during chemotherapy until the two-months check-up after chemotherapy while red blood cell aggregation (stasis & low shear), hemoglobin, and hematocrit showed a continuous but nonsignificant increase. The mean plasma viscosity, instead, declined into the normal range after the 4th cycle of chemotherapy (1.33 +/- 0.1 mPas) in patients without thrombosis. In contrast, mean plasma viscosity was increased to 1.48 +/- 0.1 mPas at the time of deep vein thrombosis diagnosis during chemotherapy. In the ovarian cancer patients of this study, the development of deep vein thrombosis postoperatively and during chemotherapy was associated with a hematocrit-independent increase in blood viscosity characterized by a high plasma viscosity and normal or low hematocrit, which was present before primary surgery as well as at the time of deep vein thrombosis diagnosis.