Aspirin for prophylaxis against venous thromboembolism after orthopaedic oncologic surgery

Background: Patients who undergo orthopaedic oncologic surgical procedures are at increased risk of developing a venous thromboembolism (VTE). Guidelines from surgical societies are shifting to include aspirin as a postoperative VTE prophylactic agent. The purpose of this study was to review our experience using aspirin as postoperative VTE prophylaxis for orthopaedic oncologic surgical procedures. Methods: This study was a retrospective review of patients diagnosed with a primary malignant soft-Tissue or bone tumor or metastatic carcinoma. Demographic information, histopathologic diagnosis, VTE history, surgical procedure, and VTE prophylaxis were analyzed. VTE rates in the overall and prophylactic-specific cohorts were recorded and compared. Results: A total of 142 distinct surgical procedures in 130 patients were included. VTE prophylaxis with aspirin was used after 103 procedures, and non-Aspirin prophylaxis was used after 39. In 33 cases, imaging was used to investigate for VTE because of clinical signs and symptoms. VTE developed after 7 (4.9%) of the 142 procedures. There were 6 deep venous thromboses (DVTs) and 1 pulmonary embolism, and 2 of the VTEs presented in patients with a VTE history. VTE developed in 2.9% (3) of the 103 aspirin cases and 10.3% (4) of the 39 non-Aspirin cases. No patient in the aspirin group who had been diagnosed with metastatic carcinoma, malignant soft-Tissue sarcoma, lymphoma, or multiple myeloma developed a VTE. Risk factors for VTE development included diabetes mellitus (odds ratio [OR] = 10.40, 95% confidence interval [CI] = 1.61 to 67.30), a history of VTE (OR = 7.26, 95% CI = 1.19 to 44.25), postoperative transfusion (OR = 34.50, 95% CI = 3.94 to 302.01), and estimated blood losses of 250 mL (OR = 1.50, 95% CI = 1.11 to 2.03), 500 mL (OR = 2.26, 95% CI = 1.23 to 4.13), and 1,000 mL (OR = 5.10, 95% CI = 1.52 to 17.04). Conclusions: Aspirin may be a suitable and effective option for VTE chemoprophylaxis in patients treated with orthopaedic oncologic surgery, especially those diagnosed with a soft-Tissue sarcoma. Research with a more advanced study design is required. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.