YEARS Algorithm for Diagnosis of Suspected Pulmonary Embolism in Patients With Cancer

The YEARS algorithm safely spared 22% of patients with cancer and suspected pulmonary embolism from computed tomographic pulmonary angiography. In the randomised Hydra trial (n=698, 21 hospitals across six European countries), within 90 days of ruling out embolism the primary outcome occurred in 5 of 282 patients (1.8%) managed by the algorithm versus 15 of 273 (5.5%) sent directly to CT; the absolute risk difference of -3.7% (99.9% CI -8.8 to 1.4) fell within the prespecified 2.6% margin. This was a NONINFERIORITY trial: the numerically lower event rate in the YEARS group does not demonstrate that the strategy is better, only that it is not worse. The proportion of negative CT scans did not differ between groups (P=.93).