<p>Atrial fibrillation is the most common cardiac arrhythmia and is a major risk factor for ischemic stroke. Atrial fibrillation and ischemic stroke are major cardiovascular complications in cancer patients, who have a higher burden and worse outcomes than the general population. Clinical risk stratification scores for stroke and bleeding, commonly used in the general population to estimate thromboembolic and bleeding risk, respectively, are less well validated in cancer patients, who have historically been excluded in clinical trials. There is a lack of consensus opinion on how to effectively risk-stratify cancer patients based on the currently available tools and a need for cancer-specific scores that offer a tailored approach to each patient in order to more effectively stratify ischemic stroke and bleeding risk in this cohort of patients. Cancer-mediated physiologic changes and adverse effects of antineoplastic therapy have been implicated as etiologies of the increased risk for both atrial fibrillation and ischemic stroke. Risk stratifying scores such as CHA₂DS₂-VASc and HAS-BLED, commonly used in the general population, are less well validated in cancer patients. There is a need for cancer-specific scores that can more effectively stratify ischemic stroke and bleeding risk in cancer patients, although given the heterogeneity of cancers, whether a “one score fits all” is uncertain.</p>