Just Do It: Changing our Culture to Embrace Optimal Perioperative Venous Thromboembolism Chemoprophylaxis for Abdominal and Pelvic Cancer Patients

Abstract

Early in the 21st century, postoperative venous thromboembolism (VTE), deep vein thrombosis (DVT), and pulmonary embolism (PE) continue to plague roughly 2.5– 10 % of abdominopelvic cancer patients. Cancer patients are an especially high-risk group, and VTE is the most common cause of early postoperative mortality, accounting for half of all deaths within 30 days after abdominopelvic cancer surgery. Given that half of all VTE events occur after hospital discharge, there has been long-standing interest in extended chemoprophylaxis (ECP), typically for 28 days postoperatively. The hypothesis that ECP is more efficacious in preventing VTE than traditional hospital-only based prophylaxis has proven true; ECP also has been proven safe. Both randomized and large observation studies have shown that ECP after abdominopelvic cancer surgery significantly decreases VTE events but does not significantly increasing the risk of bleeding. Moreover, major organizations, such as the American Society of Chest Physicians (ACCP), American Society of Clinical Oncology (ASCO), and the National Comprehensive Cancer Network (NCCN), have published practice guidelines that recommend ECP. Despite this unified expert consensus regarding the benefit of ECP nationally, these recommendations have not been embraced and adoption of ECP has been poor. For example, Merkow et al. examined the adherence to postdischarge VTE prophylaxis in Medicare beneficiaries undergoing colorectal cancer surgery and found a compliance rate of a paltry 1.5 % overall. In this issue of Annals of Surgical Oncology, we are presented with two studies examining issues integral to the implementation of ECP into clinical practice. The first, by Fagarasanu et al., is a meta-analysis reexamining the efficacy and potential risk of ECP and represents the highestquality level of evidence supporting ECP to date. The second, by Krell et al., examines the operationalization of ECP using a Michigan statewide registry, highlighting that ECP has not been widely adopted. Fagarasanu et al. reported the results of a well-performed systematic review and meta-analysis examining the efficacy of ECP. The authors, not surprisingly, found a significant reduction of proximal DVT, and all VTE, with ECP, with no increased rate of major bleeding. The three randomized control trials referenced in the Fagarasanu et al. meta-analysis are summarized below. The ENOXACAN-II study, by Bergqvist et al., randomized patients to ECP with low molecular weight heparin (LMWH), enoxaparin, or standard duration LMWH prophylaxis and found a lower rate of VTE in the ECP group of 4.8 versus 12.0 % in controls. Of note, there was persistence of the protective effect at 3 months. In the European multinational CANBESURE study by Kakkar et al., patients were randomized to ECP with bemiparin, an ultraLMWH associated with a lower risk of bleeding than LMWH, or standard duration bemiparin prophylaxis, and similarly found a lower rate of major VTE in the ECP group of 0.8 versus 4.6 % in controls; however, there was no difference in a composite outcome of DVT, nonfatal PE, and all-cause mortality. Finally, in Vedovati et al., patients Society of Surgical Oncology 2016