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.