Dermatan sulphate for the prevention of postoperative venous thromboembolism in patients with cancer

Background: Patients undergoing surgery for cancer are at high risk for venous thromboembolism (VTE). Agents that selectively inhibit thrombin, such as dermatan sulphate, have potential for a favourable benefit-risk ratio in the prevention of this complication. Methods: Patients scheduled for elective abdominal, thoracic, gynecologic or urologic surgery for cancer resection, were randomised to dermatan sulphate (600 mg intramuscularly on the second day before surgery, then 300 mg once daily), or calcium heparin (5000 IU subcutaneously t.i.d., starting 2 hours before operation). Both treatments were continued until postoperative day 7 or until adequate mobilisation was achieved. Bilateral venography was scheduled at the end of treatment. Venograms were centrally assessed in blind conditions. The study outcomes were VTE (venographically proven deep vein thrombosis [DVT] or symptomatic, objectively confirmed pulmonary embolism) and bleeding complications. Results: At 27 centres, 842 patients were randomised and underwent surgery (418 dermatan sulphate, 424 heparin). Efficacy was assessed in 521 patients with adequate venography and/or confirmed pulmonary embolism. DVT was observed in a total of 96 patients; symptomatic non-fatal pulmonary embolism developed in 2 patients (one per group), who also had DVT at venography. Postoperative VTE occurred in 40 of 267 patients on dermatan sulphate, 15.0%, versus 56 of 254 patients on heparin, 22.0% (p = 0.033). Relative risk reduction was 32.7% (95% confidence interval, 3.1 to 53.2%). The rate of bleeding complications in all operated patients was 6.9% with dermatan sulphate and 7.5% with heparin (confidence interval for the absolute risk difference, -4.1 to 2.9%). The inhospital mortality rate was 1.2% and 1.4%, respectively. Conclusions: In oncologic surgery, dermatan sulphate prevents VTE more effectively than heparin without increasing bleeding complications.