Eikelboom JW, Connolly SJ, Bosch J, et al. – Because patients who receive antithrombotic medications are at risk of bleeding—which can be the first sign of underlying cancers—researchers evaluated new cancers diagnosed in relation to gastrointestinal (GI) or genitourinary bleeding among patients enrolled in the Cardiovascular Outcomes for People Using Anticoagulation Strategies trial, and also investigated the hazard of new cancer diagnosis after bleeding at these sites. The study sample consisted of nearly 27,400 patients (mean age: 68 years; 21% women). During a mean follow-up period of 23 months, ~10% of patients experienced any bleeding (major and minor). Further, cancer was diagnosed in 1,084 patients during follow-up. Among those who experienced bleeding, ~10% received subsequent cancer diagnoses. The investigators found that GI bleeding was linked to a 20-fold higher hazard of new GI cancer diagnosis (7.4% vs 0.5%; HR: 20.6; 95% CI: 15.2-27.8), and 1.7-fold higher hazard of new non-GI cancer diagnosis (3.8% vs 3.1%; HR: 1.70; 95% CI: 1.20-2.40). In addition, genitourinary bleeding was linked to a 32-fold higher hazard of new genitourinary cancer diagnosis (15.8% vs 0.8%; HR: 32.5; 95% CI: 24.7-42.9), and urinary bleeding was correlated with a 98-fold higher hazard of new urinary cancer diagnosis (14.2% vs 0.2%; HR: 98.5; 95% CI: 68.0-142.7). Non-GI, non-genitourinary bleeding was associated with a 3-fold higher hazard of non-GI, non-genitourinary cancers (4.4% vs 1.9%; HR: 3.02; 95% CI: 2.32-3.91). Overall, in patients with atherosclerosis who received antithrombotic therapy, any GI or genitourinary bleeding was linked to higher rates of new cancer diagnosis. Thus, according to the investigators, any GI or genitourinary bleeding warrants investigation for cancers at these sites.