Screening Chest CT Prior to Allogenic Hematopoietic Stem Cell Transplantation

Abstract

Pulmonary complications constitute a major cause of morbidity and mortality in the post-allogenic hematopoietic stem cell transplantation (alloHSCT) period. Although chest X-ray (CXR) is customarily used for screening, we have used chest computed tomography (CT) scans. To characterize the prevalence of abnormalities and explore their impact on alloHSCT eligibility and outcomes post-transplantation, we conducted a retrospective analysis using real-world data collected at our center for adult patients who were evaluated for alloHSCT between January 2013 and December 2020 and identified 511 eligible patients. The most common primary disease was acute myeloid leukemia, in 49% of patients, followed by myelodysplastic syndrome (23%), lymphoma (11%), and acute lymphocytic leukemia (10%). Abnormal screening chest CT results were found in 199 patients (39%). The most frequent detected abnormality was pulmonary nodule, in 78 patients (35%), followed by consolidation in 42 (19%), ground-glass opacification in 33 (15%), bronchitis and bronchiolitis in 25 (11%), pleural effusions in 14 (6%), and new primary cancer in 7 (2%). CXR detected abnormalities in only approximately one-half of the patients (48%) with an abnormal chest CT scan. Among the 199 patients with an abnormal chest CT scan, 98 (49%) underwent further assessment and/or intervention before transplantation. The most common workup was pulmonary consultation in 32%, followed by infectious diseases consultation in 24%. Lung biopsy was obtained in 20%, and antimicrobial therapy was initiated after confirming an infection diagnosis in 20%. Patients with an abnormal chest CT scan demonstrated worse overall survival (P = .032), nonrelapse mortality (P = .015), and pulmonary-related mortality (P < .001) compared to those with a normal chest CT scan. Our study suggests that pretransplantation screening chest CT is beneficial in uncovering invasive infections and underlying malignancies and allows for appropriate interventions before alloHSCT to prevent potentially serious post-transplantation complications without causing a delay in alloHSCT. Nevertheless, abnormal CT findings prior to transplantation may be associated with overall worse prognosis.

Keywords: Allogenic transplantation; Pulmonary complications; Screening chest CT.