The cumulative incidence of venous thromboembolism at 6 months was 2.7% and at 12 months was 3.7% in patients with a new cancer diagnosis.
In a large, nationally representative US cohort of over 1.6 million patients, the 1-year cumulative incidence of cancer-associated VTE was 3.7% and was independently associated with increased mortality.
Prior epidemiological studies on cancer-associated venous thromboembolism (VTE) were limited by homogenous patient populations. We leverage Cosmos, a collaborative dataset of Epic electronic health record systems, to conduct an updated evaluation of cancer-associated VTE in the United States (US). Cosmos includes patients from all 50 states, and the dataset is representative of the US census in terms of age, race, ethnicity, and insurance coverage. We included patients in the US with a new cancer diagnosis between 2018 and 2023. We computed the cumulative incidence of VTE at 6 and 12 months after the diagnosis date and used Cox regression to identify risk factors and examine the association between VTE type within the first year and mortality. We identified 1 628 626 patients, with a cumulative incidence of VTE at 6 months of 2.7% and at 12 months of 3.7%. Major risk factors included prior VTE, cancer type, advanced stage, and chemotherapy-based treatment regimens. The occurrence of VTE within the first year of cancer diagnosis was independently associated with increased mortality.
Lam et al. (2026) studied this question. The cumulative incidence of venous thromboembolism at 6 months was 2.7% and at 12 months was 3.7% in patients with a new cancer diagnosis.