Background: Venous thromboembolism (VTE) is a major complication in patients with malignant tumors and orthopedic disorders. Although it is known that patients undergoing surgery for orthopedic oncology are at an increased risk of thromboembolic events, only few studies have investigated this risk in detail. Therefore, the aim of this study was to determine the incidence and risk factors for preoperative VTE in orthopedic oncology patients.
Methods: We retrospectively reviewed the medical records of 270 patients who underwent surgical procedures, including biopsy for orthopedic oncology, have undergone measurements of preoperative D-dimer levels, and were subsequently screened for VTE by lower extremity venous ultrasonography and/or contrast-enhanced computed tomography scans. Statistical analyses were performed to examine the incidence and risk factors for VTE. Receiver operating characteristic (ROC) analysis was performed to verify the D-dimer cutoff value for the diagnosis of VTE.
Results: Overall, 199 patients (103 with primary soft tissue sarcomas, 38 with primary bone sarcomas, 46 with metastatic tumors, and 12 with hematologic malignancies) were included. D-dimer levels were high in 79 patients; VTE was detected in 19 patients (9.5%). Multivariate analysis indicated that age ≥60 years (P = 0.021) and tumor location in the lower limbs (P = 0.048) were independent risk factors for VTE. ROC analysis showed that the D-dimer cutoff value for the diagnosis of VTE was 1.53 µg/mL; the sensitivity and specificity were 89.5% and 79.4%, respectively.
Conclusions: Our study indicated that age and tumor location in the lower limbs were independent risk factors for preoperative VTE in orthopedic oncology patients. D-dimer levels were not associated with VTE in the multivariate analysis, likely because they are affected by a wide variety of conditions, such as malignancy and aging. Patients with high D-dimer levels and the identified risk factors are at an increased risk of preoperative VTE, and additional ultrasonography should be considered.
Trial registration: Our study was approved by the institutional review board. The registration number is B200600056. The registration date was July 13, 2020.