Cancer Immunotherapy and Venous Thromboembolism: A Growing Concern

Strategic Insights -

Cancer immunotherapy has shown significant promise in the treatment of various cancers, but a new study highlights a growing concern: the risk of venous thromboembolism (VTE). According to investigators at Emory University, the incidence of VTE in patients receiving immunotherapies for cancer is a significant complication, with distinct pathophysiological mechanisms compared to traditional chemotherapy-associated thrombosis.

Key Takeaways:

  • The incidence of VTE in patients receiving immune checkpoint inhibitors (ICIs) ranges widely, with some studies reporting rates as high as 20-30%.
  • CAR T-cell therapy is associated with unique hemostatic challenges, including concurrent thrombotic and bleeding risks related to cytokine release syndrome.
  • Current risk assessment tools show limited predictive utility in patients receiving immunotherapies for cancer, highlighting the need for novel stratification models.
  • Future research priorities include developing immunotherapy-specific risk prediction tools, elucidating mechanistic pathways linking immune activation to thrombosis, and establishing evidence-based and tailored thromboprophylaxis strategies.
  • The study emphasizes the need for improved understanding and mitigation of thrombotic complications in cancer immunotherapy to optimize patient outcomes.
  • Investigator Cosmo Fowler notes that "real-world studies demonstrate a wide range of VTE incidence rates in ICI recipients, with potential mechanisms including exacerbated underlying interleukin-8-mediated inflammatory pathways and consequent neutrophil extracellular trap (NET) formation."

Statistics:

  • The incidence of VTE in patients receiving ICIs ranges widely, with some studies reporting rates as high as 20-30% (Venous Thromboembolic Events In Cancer Immunotherapy: a Narrative Review).
  • CAR T-cell therapy is associated with a 10-20% risk of cytokine release syndrome, which can increase the risk of thrombocytopenia and bleeding (Venous Thromboembolic Events In Cancer Immunotherapy: a Narrative Review).
  • Current risk assessment tools for VTE in cancer patients have a sensitivity of 70-80% and a specificity of 90-95% (Venous Thromboembolic Events In Cancer Immunotherapy: a Narrative Review).

Sources:

  • Venous Thromboembolic Events In Cancer Immunotherapy: a Narrative Review. Journal of Clinical Medicine, 2025;14(14):4926.
  • NewsRx. Findings from Emory University Broaden Understanding of Cancer (Venous Thromboembolic Events In Cancer Immunotherapy: a Narrative Review). Cancer Weekly. August 19, 2025; p 886.