Background:Adrenocortical carcinoma is a rare malignancy with a poor prognosis. We hypothesized that patients with adrenocortical carcinoma are at high risk for venous thromboembolism, given the numerous risk factors such as malignancy, abdominal surgery, immobility and hormonal excess. The aim of this study was to determine retrospectively the incidence of venous thromboembolisms after surgical treatment in patients with adrenocortical carcinoma.Materials and methods:A retrospective study was performed, collecting data from all patients diagnosed with adrenocortical carcinoma from 2003 to 2018 at the Radboud University Medical Centre, The Netherlands.Results:In 34 patients, eight postoperative venous thromboembolisms, all pulmonary embolisms, were diagnosed in the first 6 months after adrenalectomy (23.5%). In addition, one patient developed pulmonary embolism just prior to surgery and one patient 7 years after surgery. Five of the eight patients with postoperative venous thromboembolisms presented with symptomatic pulmonary embolism whereas the other three pulmonary embolisms were incidentally found on regular follow up CT scans. Seven of the eight venous thromboembolisms occurred within 10 weeks after surgery. Seven of the eight patients had advanced stage adrenocortical carcinoma and four patients already received low-molecular weight heparin during the development of the venous thromboembolism. There was one case of fatal pulmonary embolism in a patient with a cortisol producing tumor with pulmonary metastases, despite the use of a therapeutic dose thromboprophylaxis.Conclusion:Patients with adrenocortical carcinoma are at high risk of developing postoperative venous thromboembolisms. Prolonged postoperative thromboprophylaxis could be considered in these patients.