HOUSTON — Is immune checkpoint inhibitor (ICI) therapy associated with higher rate of venous thromboembolism (VTE) compared with cytotoxic chemotherapy (chemo) in patients with comparable cancer type, staging and comorbidities?
That was the question addressed in a new study from Baylor College of Medicine. The study team, which also included representation from the VA Boston Healthcare System, used data from the national VA healthcare system database from 2016 to 2021. The propensity score (PS)-weighted retrospective cohort study was conducted to compare the incidence of VTE in patients with selected Stage III/IV cancer receiving first-line ICI versus chemo.
Results, published in the American Journal of Hematology, found that, among comparable advanced cancers, the 1,823 receiving first-line ICI therapy and the 6,345 receiving first-line chemo had similar rates of VTE— 8.49% for ICI and 8.36% for chemo at 6 months. The researchers advised that the weighted HR was 1.06 (95% CI 0.88-1.26) for ICI versus chemo.1
“In a subgroup analysis restricted to lung cancers, first-line ICI/chemo (n = 828), ICI monotherapy (n = 428), and chemo monotherapy (n = 4371) had similar rates of VTE (9.60% for ICI/chemo, 10.04% for ICI, and 8.91% for chemo at 6 months),” the study reported. “The weighted HR was 1.05 (95% CI 0.77-1.42) for ICI versus chemo, and 1.08 (95% CI 0.83-1.42) for ICI/chemo versus chemo.”
The authors concluded that “ICI as a systemic therapy has a similarly elevated risk as cytotoxic chemo for VTE occurrence in cancer patients. This finding can inform future prospective studies exploring thromboprophylaxis strategies.”
- Li A, May SB, La J, Martens KL, Amos CI, Flowers CR, Do NV, Brophy MT, Chitalia V, Ravid K, Gaziano JM, Fillmore NR. Venous thromboembolism risk in cancer patients receiving first-line immune checkpoint inhibitor versus chemotherapy. Am J Hematol. 2023 May 10. doi: 10.1002/ajh.26954. Epub ahead of print. PMID: 37161855.
