To evaluate a modified emergency severity index (mESI)-based triage of cancer patients with coronavirus disease 2019 (COVID-19) in the emergency department (ED) and determine the associations between mESI level and ED disposition, hospital length of stay, and overall survival.

Medical records were retrospectively reviewed for all patients who presented to our institution's ED between March 22, 2020, and March 12, 2021, and tested positive for SARS-CoV-2.

A total of 306 cancer patients tested positive for SARS-CoV-2, with 45% of patients triaged to level 2 (emergent) and 55% to level 3 (urgent). Among all patients, 61.8% were admitted to the hospital, 15.7% were admitted to the intensive care unit, 2.9% were sent for observation, and 19.6% were discharged. Although demographic and clinical characteristics did not significantly vary by triage level, we observed significant differences in ED length of stay (urgent = 6.67 h, emergent = 5.97 h; p < 0.01). Hospital and intensive care unit admission rates were also significantly higher among emergent patients than among urgent patients (p < 0.05). There were 75 deaths (urgent = 32; emergent = 43), and the 30-day mortality rate was significantly higher among emergent patients (urgent = 8%, emergent = 15%; p < 0.05). The mESI level persisted as a significant factor associated with overall survival (hazard ratio = 1.7, 95% confidence interval = 1.09–2.81) in multivariable analysis.

The mESI level is associated with ED disposition, ED length of stay, and overall survival in cancer patients presenting with COVID-19. These results indicate that the mESI triage tool can be effectively used in cancer patients with COVID-19, whose condition can rapidly deteriorate.