A. What is the overall risk for VTE in this patient population and what are the factors that increase VTE risk in this patient population?
B. What is the optimal VTE prophylaxis protocol in this patient population when also taking into consideration bleeding risk?
Tanis Worthy, Michelle Ghert, M. Hardian Basuki, Felasfa Wodajo, Andreas Leithner, Panayiotis J. Papagelopoulos, Jashvant Poeran.
Response/Recommendation: Patients undergoing sarcoma surgery have a high risk of venous thromboembolism (VTE) with multiple common risk factors relating to the patient population, surgery, and complications. Patients should have chemoprophylaxis with either low-molecular-weight heparin (LMWH) or aspirin (ASA) unless very high bleeding risk, combined with pneumatic compression.
Strength of Recommendation: Limited.
Rationale: Major orthopaedic surgeries and oncological patients have increased risk for VTE, with the mean incidence of all VTE events in orthopaedic oncology patients being 10.7% (1.1% to 27.7%). Risk factors for increased events include endoprosthetic replacements, hip and pelvic resections, surgical procedures taking longer than 3 hours, and chemotherapy1, all of which are common with sarcoma surgeries. Higher preoperative white blood cell count (odds ratio [OR] 1.15, 95% confidence interval [CI] 1.01-1.29) and post-operative wound complications (OR 5.01, 95% CI 1.93-13.55) were found to be independent risk factors for VTE2. The risk of wound complications increased significantly in patients with primary bone sarcoma who received chemical prophylaxis (OR 2.21, 95% CI 1.00-4.87)2. Regarding pulmonary embolism (PE) specifically, primary malignant bone tumours, bone tumour resections and prosthetic reconstructions had significantly higher risk than soft tissue tumours or soft tissue tumour resections3.
There is varied evidence on whether chemoprophylaxis will decrease VTE rates. One study stated there was no identified significant difference with use of chemoprophylactic agent and incidence of VTE in patients undergoing mega-endoprosthetic reconstruction after cancer resection4. However, it was also found that in populations where there was consistent and careful prophylaxis until time of weight-bearing, there was a low occurrence of VTE events (1.1%)5. As stated above, chemoprophylaxis may increase wound complications, which in turn may increase chance of VTE events due to prolonged immobilization or additional surgeries. This would suggest that there should be allowance within this recommendation to modify the treatment depending on independent patient risk factors regarding prophylactic treatment.
There is limited literature on optimal prophylaxis. When looking at patients that had hip replacements for oncologic indications, there is a low rate of deep vein thrombosis (DVT) when pneumatic compression devices are supplemented with LMWH6. There was no significant difference regarding DVT rate when ASA versus LMWH was used to supplement the pneumatic compressions devices7.
Given that there is multiple risk factors and a high overall risk within the population, and varied evidence suggesting either no improvement, to improvement with a combination of pneumatic and chemoprophylaxis, it would be recommended to give chemoprophylaxis unless specific patient factors such as high bleeding risk suggest otherwise. The type of chemoprophylaxis can be surgeon’s choice, with ASA and LMWH being viable possibilities. Routine prophylaxis until full weight-bearing has a chance of decreasing the possibility of VTE events in a high-risk population.
References:
1. Lex JR, Evans S, Cool P, et al. Venous thromboembolism in orthopaedic oncology. Bone Joint J. 2020;102-B(12):1743-1751. doi:10.1302/0301-620X.102B12.BJJ-2019-1136.R3
2. Kaiser CL, Freehan MK, Driscoll DA, Schwab JH, Bernstein KDA, Lozano-Calderon SA. Predictors of venous thromboembolism in patients with primary sarcoma of bone. Surg Oncol. 2017;26(4):506-510. doi:10.1016/j.suronc.2017.09.007
3. Ogura K, Yasunaga H, Horiguchi H, Ohe K, Kawano H. Incidence and risk factors for pulmonary embolism after primary musculoskeletal tumor surgery. Clin Orthop Relat Res. 2013;471(10):3310-3316. doi:10.1007/s11999-013-3073-9
4. Ramo BA, Griffin AM, Gill CS, et al. Incidence of symptomatic venous thromboembolism in oncologic patients undergoing lower-extremity endoprosthetic arthroplasty. J Bone Joint Surg Am. 2011;93(9):847-854. doi:10.2106/JBJS.H.01640
5. Ruggieri P, Montalti M, Pala E, et al. Clinically significant thromboembolic disease in orthopedic oncology: an analysis of 986 patients treated with low-molecular-weight heparin. J Surg Oncol. 2010;102(5):375-379. doi:10.1002/jso.21645
6. Nathan SS, Simmons KA, Lin PP, et al. Proximal deep vein thrombosis after hip replacement for oncologic indications. J Bone Joint Surg Am. 2006;88(5):1066-1070. doi:10.2106/JBJS.D.02926
7. Patel AR, Crist MK, Nemitz J, Mayerson JL. Aspirin and compression devices versus low-molecular-weight heparin and PCD for VTE prophylaxis in orthopedic oncology patients. J Surg Oncol. 2010;102(3):276-281. doi:10.1002/jso.21603