Real-world thrombotic and survival outcomes with ESAs in cancer-related anemia

Erythropoiesis-stimulating agents (ESAs) are commonly used to treat cancer-related anemia by increasing hemoglobin levels and reducing transfusion requirements. However, randomized trials and meta-analyses have linked ESA use to increased thrombotic risk. Contemporary real-world data across diverse cancer populations and ESA formulations remain limited. We conducted a retrospective cohort study using the TriNetX Research Network (from 1 January 2015 to 31 July 2024) evaluating adult patients with cancer-related anemia. Patients receiving ESAs were propensity score-matched 1:1 with patients not receiving ESAs based on demographics, cancer type, and comorbidities. Individuals with previous thrombotic events or anticoagulant use were excluded. Outcomes included incident deep vein thrombosis (DVT), pulmonary embolism (PE), new anticoagulant use, and 1-year survival. Risk differences, relative risks, and Kaplan-Meier survival analyses were performed. After matching, 1606 patients were included in each cohort, with prostate, breast, bladder, colon, and kidney cancers being the predominant cancer. There was no significant difference in DVT (1.5% vs 2.1%; P = .19) or PE (0.75% vs 1.1%; P = .27) between ESA and non-ESA groups. New anticoagulant use was significantly lower in patients treated with ESAs (6.3% vs 10.2%; risk ratio, 0.52; 95% confidence interval [CI], 0.49-0.78; P < .001). One-year survival was higher in the ESA cohort (73% vs 69%; hazard ratio, 0.82; 95% CI, 0.72-0.94; P = .004). In this large real-world cohort, ESA use was not associated with increased short-term thrombotic risk and was associated with lower anticoagulant use and improved 1-year survival. These findings suggest that guideline-concordant ESA use may be safe in selected patients with cancer-related anemia.