Lymphadenectomy is associated with an increased risk of postoperative venous thromboembolism in early stage endometrial cancer

Objectives: In patients undergoing surgery for early stage endometrial cancer, we sought to evaluate the effect of lymphadenectomy (LND), as well as surgical route, on the risk of postoperative venous thromboembolism (VTE). Methods: The Surveillance, Epidemiology, and End Results cancer registries (2000−2013) linked to Medicare claims follow up from 1999 to 2014 was accessed to identify those with stage I-II endometrioid endometrial cancer who underwent hysterectomy. Performance of LND, 90-day incidence of postoperative VTE, open vs minimally invasive surgery (MIS), demographics, comorbidities, grade, and stage were collected. A washout period of 12 months with no prior VTE was required. t-test, Chi square test, univariate and multivariable Poisson regression with robust variance estimator were used. Results: A total of 15,101 patients had hysterectomy for early stage endometrial cancer. LND was performed in 9004 (60%) patients. VTE was found in 486 patients. There were 346 VTEs (3.8%) in the LND group vs 140 (2.3%) in those without LND (RR = 1.67, p < 0.0001). Adjusting for age, stage, grade, comorbidities and surgical approach, LND remained a significant risk for VTE (RR = 1.7, p < 0.001). In those who underwent MIS, LND was associated with a two-fold increase in the risk of VTE (p = 0.0008) (adjusted RR = 1.99, p = 0.0014) and had a statistically comparable rate of VTE when compared to the open surgical approach (p = 0.054). Conclusions: LND is associated with an increased 90-day risk of postoperative VTE in patients undergoing surgery for early stage endometrial cancer. The need for extended postoperative VTE prophylaxis in patients undergoing LND via MIS needs further exploration.