Introduction: Deep venous thrombosis (DVT) prophylaxis is particularly important for surgical oncologists given the high rate of DVT in patients with malignancy. Additionally, DVT prophylaxis may soon be implemented by some payers as a "pay for performance" quality measure. This is a systematic review of randomized controlled trial (RCT) evidence for DVT prophylaxis in cancer patients undergoing surgery. We examine overall rates of DVT, the efficacy of high versus low-dose heparin prophylaxis, and the rate of bleeding complications.
Methods: The Medline database was searched for English language RCTs using key words DVT, venous thromboembolism, prophylaxis, and general surgery. Inclusion criteria were RCTs evaluating surgical oncology patients.
Results: Fifty-five RCTs studied DVT prophylaxis in surgery (nonorthopedic) patients. Twenty-six RCTs evaluated 7,639 cancer patients. The overall DVT rate was 12.7% for pharmacologic prophylaxis and 35.2% for controls. High-dose low-molecular weight heparin (LMWH) was more effective than low dose, lowering the DVT rate from 14.5% to 7.9% (P < 0.01). Heparin decreased the rate of proximal DVTs. Bleeding complications requiring discontinuation of prophylaxis occurred in 3% of the patients. There was no difference between LMWH and unfractionated heparin in efficacy, DVT location, or bleeding complications.
Conclusion: Using RCT data, this study demonstrates a greatly reduced DVT rate with pharmacologic prophylaxis in cancer patients, and higher doses appear more effective. Complication rates are low and should not prevent the use of prophylaxis in most patients. Finally, we found no difference between LMWH and unfractionated heparin in these RCTs. These results highlight the importance of routine pharmacologic prophylaxis in surgical patients with malignancy.