Incidence of recurrent venous thromboembolism and bleeding complications in patients with cancer and isolated distal deep vein thrombosis.

BACKGROUND: Isolated distal deep vein thrombosis (IDDVT) is a common clinical presentation of DVT. The efficacy and safety of anticoagulant therapy for the management of IDDVT in patients with cancer are unclear. We sought to assess the incidence of recurrent venous thromboembolism (VTE) and major bleeding in this patient population. METHODS: A systematic search of MEDLINE, EMBASE and PubMed, from inception to June 2, 2022 was performed. The primary efficacy outcome was recurrent VTE and the primary safety outcome was major bleeding. The secondary outcomes were clinically relevant non-major bleeding (CRNMB) and mortality. The incidence rates of thrombotic, bleeding, and mortality outcomes were pooled using random effects model and expressed as events per 100 patient-months with associated 95 % confidence intervals (CI). RESULTS: Out of a total of 5234 articles, 10 observational studies including 8160 patients with cancer and IDDVT were included in the analysis. The incidence rate of recurrent VTE was 5.65 (95 % CI: 2.09-15.30) per 100 patient-years regardless of type and duration of anticoagulant therapy. The incidence rate of major bleeding was 4.08 (95 % CI: 2.52-6.61) per 100 patient-years. The incidence rates for CRNMB and mortality per 100 patient-years were 8.11 (95 % CI: 5.56-11.83) and 30.22 (95 % CI: 22.60-40.42.89), respectively. CONCLUSION: Patients with cancer and IDDVT are at high risk of developing recurrent VTE and bleeding complications (both major bleeding and CRNMB). More studies are needed to define the optimal management for this high-risk population.

Efficacy and safety of apixaban for primary prevention of thromboembolism in patients with cancer and a central venous catheter: A subgroup analysis of the AVERT Trial.

INTRODUCTION: Central venous catheters (CVC) are associated with an increased risk of venous thromboembolism (VTE) in patients with cancer. Primary thromboprophylaxis using a direct oral anticoagulant decreases the risk of VTE in intermediate-to-high risk ambulatory cancer patients. We assessed the efficacy and safety of thromboprophylaxis with apixaban in the subpopulation of patients with cancer and a CVC in the AVERT trial. METHODS: The AVERT study was a randomized, placebo-controlled, double-blind clinical trial assessing the efficacy and safety of apixaban for primary thromboprophylaxis in patients with cancer initiating chemotherapy who were at intermediate to high risk of VTE. The primary efficacy outcome was objectively confirmed VTE within 180 days of randomization and the primary safety outcome was major bleeding. The hazard ratios (HRs) were calculated using a Cox regression model controlling for age, gender, and center. RESULTS: A total of 217 patients had a CVC and were included in the subgroup analyses with 126 and 91 patients receiving apixaban or placebo, respectively. VTE occurred in 6 (4.8%) patients in the apixaban group and 17 (18.7%) patients in the placebo group (HR 0.26; 95% CI, 0.14-0.47; p < 0.0001). Major bleeding occurred in 2 (1.6%) patients in the apixaban group and 2 (2.2%) patients in the placebo group (HR 0.69; 95% CI, 0.20-2.35; p = 0.556). CONCLUSIONS: Primary thromboprophylaxis with apixaban in patients with cancer and a CVC was associated with a reduced risk of VTE in the AVERT study population, without an increased risk of bleeding. (Funded by the CIHR and Bristol-Myers Squibb-Pfizer Alliance; NCT02048865).

Efficacy and safety of primary thromboprophylaxis for the prevention of venous thromboembolism in patients with cancer and a central venous catheter: A systematic review and meta-analysis.

BACKGROUND: Venous thromboembolism (VTE) is a leading cause of mortality in patients with cancer and is associated with significant morbidity and healthcare expenditure. The risk of VTE is increased following the insertion of a central venous catheter (CVC) for chemotherapy delivery and supportive care. The risks and benefits of primary thromboprophylaxis in patients with cancer and CVC are unclear. OBJECTIVE: We sought to assess the rates of VTE and bleeding complications and to determine the efficacy and safety of primary thromboprophylaxis in adult patients with cancer and a CVC. METHODS: A systematic search of MEDLINE, EMBASE, and all EBM was conducted. Randomized controlled trials (RCTs) of adult patients with cancer and a CVC receiving primary thromboprophylaxis compared to observation/placebo were included. The primary efficacy and safety outcomes were total VTE and major bleeding episodes, respectively. RESULTS: A total of 12 RCTs (3545 patients) were included in the analysis. The total rates of VTE were significantly lower in patients receiving thromboprophylaxis compared to those not receiving primary prevention (7.6% vs. 13%; Odds Ratio (OR) 0.51, 95% CI 0.32-0.82, p < 0.01). The rates of major bleeding complications were not higher in patients receiving thromboprophylaxis (0.9% vs. 0.6%; OR 1.12, 95% CI 0.29-4.40, p = 0.87). CONCLUSIONS: Primary thromboprophylaxis significantly reduced the risk of VTE without increasing the risk of major bleeding complications in patients with cancer and CVC. Future studies are needed to confirm these findings.