Venous thromboembolism following oncologic pancreas and liver surgery.

BACKGROUND: Venous thromboembolism (VTE) is a serious complication after hepatopancreatobiliary surgery. We investigated the incidence and timing of VTE events postoperatively and explored factors associated with VTE development. METHODS: We analyzed the SEER-Medicare database for patients with primary pancreas or liver cancer undergoing resection between 2002 and 2019. The primary outcome was VTE within 90 days postoperatively and the secondary outcomes included 90-day postoperative deep venous thrombosis and pulmonary embolism and late (91-180 days) VTE. RESULTS: We identified 17756 eligible surgeries. The median age was 73 years, 49 % were female, and 59 % underwent a pancreatoduodenectomy. In total, 1695 patients (10 %) developed VTE within six months, with 32 % within one month and 67 % within 3 months postoperatively. Variables independently associated with 90-day VTE included female sex (OR 1.14), higher Elixhauser (OR 1.06) and Caprini scores (OR 1.14), residence in metropolitan area (population >1 million vs < 250k, OR 1.32), dual Medicaid eligibility (OR 3.07), advanced stage (distant vs localized, OR 2.03), surgery type (Whipple vs partial hepatectomy, OR 1.75), and lower hospital volume (1st vs 4th quartile, OR 1.41). DISCUSSION: Patients with pancreas and liver cancer continued to experience VTE events up to 6 months following surgery. We identified clinical and sociodemographic factors for VTE risk stratification.