Introduction: Cancer patients face an elevated risk of ischemic stroke, yet predictors remain poorly defined. Cancer-associated stroke (CAS) may arise from mechanisms distinct from traditional stroke risk factors, including cancer-related hypercoagulability related to neutrophil extracellular traps (NETs). The neutrophil-to-lymphocyte ratio (NLR), a potential surrogate of NET activity, has been proposed as a thrombotic biomarker, but its predictive value for ischemic stroke in cancer patients is not established. Methods: We conducted a retrospective cohort study of adults diagnosed with pancreatic cancer at our institution between February 2019 and February 2024 and with at least 1 follow-up visit. Clinical variables, past medical history, laboratory values within one month of cancer diagnosis and prior to treatment, and cancer characteristics were collected. CAS was determined by a vascular neurologist assessment and confirmatory imaging. Stepwise Cox regression was used to identify independent factors associated with stroke within 1 year of cancer diagnosis. Results: Of 551 eligible patients (median age 69, 43% female, 86% White), 23 (4.2%) experienced CAS within a year of cancer diagnosis (median time of 42 days, interquartile range 12-199 days). Of the 23 patients with ischemic stroke, 18 (78%) patients had an embolic stroke of undetermined source, and nine patients had preceding or concomitant venous thromboembolism. Compared to patients without CAS, those with CAS had a greater prevalence of hyperlipidemia (65% vs 38%, p=0.04), metastasis at time of cancer diagnosis (78% vs 35%, p<0.001), and higher median NLR (6.1 vs 3.3 , p<0.001). Multivariable analysis identified the following independent stroke predictors: history of prior stroke (HR 4.9, 95% CI 1.41-17.06; p=0.01), metastatic disease at diagnosis (HR 6.05, 95% CI 2.1-17.3; p<0.001), and NLR (HR 1.11 per unit, 95% CI 1.05-1.17). Conclusion: Pancreatic cancer patients face high early stroke risk, with NLR at diagnosis emerging as an independent predictor of incident stroke. NLR may reflect NET-mediated hypercoagulability, and further mechanistic studies are needed to investigate the utility of NLR in CAS risk stratification and prevention.
Shoskes et al. (Thu,) studied this question.