Thromboprophylaxis in gynecologic cancer surgery: Is extended prophylaxis with low molecular weight heparin justified?

Objective: Evidence on the optimal duration of thromboprophylaxis with low molecular weight heparin after gynecologic cancer surgery is scarce and the benefits of extended prophylaxis have not been validated specifically in these patients. The aim of this study is to assess the efficacy and safety of postoperative venous thromboembolism (VTE) prophylaxis with enoxaparin 40 mg for 28 days, as recommended by international guidelines, compared to 7 days in patients undergoing surgery for gynecologic cancer.

Study Design: Prospective cohort study compared to a historic cohort of women who underwent surgery for gynecologic cancer in our center between 2004 and 2014. Pre- and postoperative screening with a routine duplex scan was done in the prospective cohort. Comparative analysis of comorbidity, surgical technique and incidence of VTE, as well as prognostic factors of events and mortality.

Results: N:571 patients (28 days: 207, 7 days: 364). No significant differences were identified between groups in regard to the factors related to VTE in our series. There were no differences in VTE incidence between groups after one month (1.9% vs 1.4%; p = 0.729), 90 days (2.4% vs 2.5%; p > 0.99) or during follow-up (Breslow p = 0.156). No deaths due to VTE at 90 days were recorded. Only one case of asymptomatic DVT was identified in the screening with duplex. The incidence of postoperative bleeding was similar in both groups (0.5% vs 2.2%; p = 0.166). The presence of a history of VTE was the only independent risk factor for VTE after one month (OR 14.31 CI 95% 2.67-76.87; p = 0.002) and 90 days (OR 8.27 CI 95% 1.65-41.45; p = 0.010). No differences were identified regarding age, other comorbidities, type of tumor, stage, surgical approach, reintervention or adjuvant therapy in the multivariate analysis.

Conclusion: Extended prophylaxis for 28 days with enoxaparin did not improve the rates of VTE following gynecologic oncological surgery in our series compared to the 7-day therapy, although neither was this extended duration associated with adverse events or mortality.