The Utility of Computed Tomography of the Chest at the Time of Induction Chemotherapy in Patients with Acute Leukemia

Background: Compared to chest X-ray, computed tomography (CT) imaging of the chest is more sensitive and specific for identifying pulmonary abnormalities. However, patients with acute leukemia routinely undergo chest X-ray before beginning chemotherapy, and the benefit of obtaining baseline chest CT remains unclear. Methods: In this retrospective study, 50 patients with newly diagnosed acute leukemia who underwent chest X-ray and chest CT without contrast before beginning induction chemotherapy were included. CT imaging reports were independently evaluated by two hematologist–oncologists for infection concern and actionability, and these assessments were compared to the actions taken by the treating physicians. Results: Regardless of the presence of chest X-ray abnormalities, chest CT identified abnormalities in 94% of patients (47/50), a significantly higher detection rate than that for chest X-ray, which demonstrated abnormalities in only 66% of patients (33/50) (p < 0.001). Of the 17 patients with normal chest X-ray findings, 14 (82%) had abnormal chest CT findings. Of these 14 patients, 10 had actionable abnormalities, and four had non-clinically significant findings. All 33 patients with abnormal chest X-ray findings also had abnormal chest CT findings, and three patients with normal chest X-ray findings also had normal chest CT findings. Of the 30 patients with normal or minimal chest X-ray findings compared to chest CT findings, 26 patients (87%) had chest CT findings that were actionable, prompting more aggressive care and/or closer monitoring. On multivariate analysis, patients with both abnormal chest X-ray and chest CT findings had worse overall survival than patients without both abnormal chest X-ray and chest CT findings (p = 0.005) Conclusions: These findings highlight a diagnostic gap, potentially supporting prospective studies on routine chest CT imaging for patients with newly diagnosed acute leukemia.