Incidence, risk factors, and outcomes of venous thromboembolism in patients undergoing surgery for retroperitoneal tumors: a propensity-matched retrospective cohort study

Background: Venous thromboembolism (VTE) is a common postoperative complication; however, the incidence and risk stratification of postoperative VTE in patients with retroperitoneal tumor remains unclear. The authors aim to quantify the incidence, identify risk factors, and determine the outcomes of VTE in patients undergoing retroperitoneal tumor surgery. Methods: The authors retrospectively reviewed the characteristics, perioperative outcomes, and overall survival (OS) of patients (VTE and non-VTE) who underwent retroperitoneal tumor surgery between 2015 and 2020. Perioperative and oncologic outcomes were compared using propensity-matching and Cox analyses. Results: Of 1223 patients with retroperitoneal tumor surgery, 2.1% had VTE. Age [odds ratio (OR) 1.140, 95% CI: 1.053-1.239, P=0.004], recurrence (OR 1.851, 95% CI: 1.241-2.761, P=0.003), and vascular resection (OR 2.036, 95% CI: 1.054-3.934, P=0.034) were independent risk factors, with significant between-group differences regarding age, recurrence, sarcoma, organ resection, vascular resection, and operation time. No between-group differences in 30-day all-cause mortality (8 vs. 4%, OR 0.657, 95% CI: 0.375-1.151, P=0.427) and major complications (12 vs. 8%, OR 0.775, 95% CI: 0.483-1.244, P=0.572) were observed. Mean hospitalization duration (20.1 vs. 22.9 days, OR 1.153, 95% CI: 1.022-1.386, P=0.033) and ICU stay (3.2 vs. 5.5 days, OR 1.193, 95% CI: 1.034-1.347, P=0.012) were shorter in non-VTE versus VTE, respectively, with inferior OS (hazard ratio 2.090, 95% CI: 1.014-4.308, P=0.046) in VTE. Conclusions: Age, recurrence, and vascular resection are positively associated with VTE, which is associated with inferior OS.