Anticoagulation for the long term treatment of venous thromboembolism in patients with cancer

For the long term treatment of venous thromboembolism in patients with cancer, low molecular weight heparin compared to vitamin K antagonist appears to reduce venous thromboembolic events but not death.

The quality of evidence is downgraded by study limitations (unclear allocation concealment and lack of blinding).

Summary

A Cochrane review included 16 studies with a total of 5 167 subjects with cancer and with venous thromboembolism (VTE).

Low molecular weight heparins (LMWHs) versus vitamin K antagonists (VKAs): There were no differences in mortality up to 12 months of follow-up (RR 1.00, 95% CI 0.88 to 1.13; 5 studies, n=1 747), in major bleeding (RR 1.09, 95% CI 0.55 to 2.12; 4 studies, n=1 712), minor bleeding (RR 0.78, 95% CI 0.47 to 1.27; 4 studies, n=1 712; statistical heterogeneity I²=78%), or thrombocytopenia (RR 0.94, 95% CI 0.52 to 1.69; 1 study, n=138) between LMWHs and VKAs. LMWHs reduced the recurrence of VTE compared to VKAs (RR 0.58, 95% CI 0.43 to 0.77; 5 studies, n=1 781). Direct oral anticoagulants (DOACs) versus VKAs: There were no differences in mortality (RR 0.93, 95% CI 0.71 to 1.21; 4 studies, n=1 031), recurrent VTE (RR 0.66, 95% CI 0.33 to 1.31; 4 studies, n=1 022), major bleeding (RR 0.77, 95% CI 0.38 to 1.57; 4 studies, n=1 030), or minor bleeding (RR 0.84, 95% CI 0.58 to 1.22; 4 studies, n=1 030). DOACs versus LMWH: One study found no difference in mortality up to 12 months of follow-up (RR 1.07, 95% CI 0.92 to 1.25; 1 study, n=1 016), but there was a likely reduction with DOACs in VTE recurrence up to 12 months of follow-up (RR 0.69, 95% CI 0.47 to 1.01; 1 study, n=1 016) compared to LMWHs. DOAC increased major bleeding at 12 months of follow-up compared to LMWH (RR 1.71, 95% CI 1.01 to 2.88; 1 study, n=1 016) and likely increased minor bleeding up to 12 months of follow-up compared to LMWH (RR 1.31, 95% CI 0.95 to 1.80; 1 study, n=1 016). Idraparinux versus vitamin K antagonists: One study (n=284) compared once-weekly subcutaneous injection of idraparinux versus standard treatment (parenteral anticoagulation followed by warfarin or acenocoumarol) for 3 or 6 months. There was no difference between idraparinux and VKAs in mortality at 6 months (RR 1.11, 95% CI 0.78 to 1.59), VTE recurrence at 6 months (RR 0.46, 95% CI 0.16 to 1.32) or major bleeding (RR 1.11, 95% CI 0.35 to 3.56).

The following decision support rules contain links to this evidence summary:

• Low molecular weight heparin as anticoagulant for patients with venous thromboembolism and cancer

Ədəbiyyat

1. Kahale LA, Hakoum MB, Tsolakian IG et al. Anticoagulation for the long-term treatment of venous thromboembolism in people with cancer. Cochrane Database Syst Rev 2018;(6):CD006650.