BackgroundTriage procedures have been implemented to limit hospital access and minimize infection risk among patients with cancer during the coronavirus disease (COVID‐19) outbreak. In the absence of prospective evidence, we aimed to evaluate the predictive performance of a triage system in the oncological setting.Materials and MethodsThis retrospective cohort study analyzes hospital admissions to the oncology and hematology department of Udine, Italy, during the COVID‐19 pandemic (March 30 to April 30, 2020). A total of 3,923 triage procedures were performed, and data of 1,363 individual patients were reviewed.ResultsA self‐report triage questionnaire identified 6% of triage‐positive procedures, with a sensitivity of 66.7% (95% confidence interval [CI], 43.0%–85.4%), a specificity of 94.3% (95% CI, 93.5%–95.0%), and a positive predictive value of 5.9% (95% CI, 4.3%–8.0%) for the identification of patients who were not admitted to the hospital after medical review. Patients with thoracic cancer (odds ratio [OR], 1.69; 95% CI, 1.13–2.53, p = .01), younger age (OR, 1.52; 95% CI, 1.15–2.01, p < .01), and body temperature at admission ≥37°C (OR, 9.52; 95% CI, 5.44–16.6, p < .0001) had increased risk of positive triage. Direct hospital access was warranted to 93.5% of cases, a further 6% was accepted after medical evaluation, whereas 0.5% was refused at admission.ConclusionA self‐report questionnaire has a low positive predictive value to triage patients with cancer and suspected severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) symptoms. Differential diagnosis with tumor‐ or treatment‐related symptoms is always required to avoid unnecessary treatment delays. Body temperature measurement improves the triage process's overall sensitivity, and widespread SARS‐CoV‐2 testing should be implemented to identify asymptomatic carriers.Implications for PracticeThis is the first study to provide data on the predictive performance of a triage system in the oncological setting during the coronavirus disease outbreak. A questionnaire‐based triage has a low positive predictive value to triage patients with cancer and suspected severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) symptoms, and a differential diagnosis with tumor‐ or treatment‐related symptoms is mandatory to avoid unnecessary treatment delays. Consequently, adequate recourses should be reallocated for a triage implementation in the oncological setting. Of note, body temperature measurement improves the overall sensitivity of the triage process, and widespread testing for SARS‐CoV‐2 infection should be implemented to identify asymptomatic carriers.