Diagnosis of Incident Cancer after Cryptogenic Stroke: An Exploratory Analysis of the ARCADIA Randomized Trial

ObjectivesThe objective of this study was to estimate the incidence, timing, and type of new cancer diagnosis among patients with cryptogenic stroke.MethodsWe used data from the ARCADIA trial, which enrolled patients with cryptogenic stroke and atrial cardiopathy. Participants were prospectively followed, and serious adverse events were assessed every 3 months or sooner if investigators were alerted between visits to an event. Kaplan-Meier statistics were used to estimate the cumulative incidence of a cancer diagnosis within the first year after randomization.ResultsAmong 878 participants without baseline history of cancer, 13 (1.5%) were diagnosed with incident cancer in the year after randomization, comprising 12 solid cancers (3 prostate, 2 breast, 2 gastrointestinal, and 5 other primary sites) and 1 hematologic cancer (non-Hodgkin lymphoma). The cumulative incidences of a cancer diagnosis were 0% at 3 months, 0.6% (95% CI 0.2%-1.5%) at 6 months, and 2.0% (95 CI 1.1%-3.4%) at 1 year. The median time from index stroke to cancer diagnosis was 261 days (interquartile range 183-358).DiscussionIn a multicenter cryptogenic stroke cohort with prospective follow-up, the 1-year cumulative incidence of a cancer diagnosis was 2%. This rate may be an underestimation because of the clinical trial population and exclusion of cancers diagnosed immediately after stroke.