Indolent Presentations of Leukemic Lung Disease in Acute Myeloid Leukemia

BackgroundPatients with active acute myelogenous leukemia (AML) are at risk for leukemic infiltration (LI) into the lung and acute tumor lysis pneumopathy (ATLP) following chemotherapy. Fulminant presentations of these leukemic lung diseases are well-described, but indolent forms have not yet been studied. Therefore, we sought to elucidate the clinical features of mild-to-moderate LI and ATLP. MethodsA retrospective cohort analysis was performed on 51 hospitalized patients with AML, circulating blast count [≥]3%, non-critical illness, and receipt of bronchoscopy between 2015-2019. Diagnoses of LI and ATLP were made via retrospective chart review by a multidisciplinary team of physicians. Results19 cases of leukemic lung disease were identified: 14 with LI and 5 with ATLP. The clinical presentations closely resembled pneumonia, with the majority demonstrating respiratory symptoms (63%), hypoxemia (63%), fever (84%), and pulmonary opacities (100%). All patients were presumptively diagnosed with infection, leading to an average of 18 days of broad-spectrum antibiotic therapy and multiple instances of delayed chemotherapy in treatment candidates. Although most patients were near the end-of-life (90% died within 1 year), transitions to comfort care were infrequent (25%) and hospitalizations were protracted (median 25 days). ConclusionsLI and ATLP are common yet under-recognized pulmonary complications in patients with active AML. When presenting indolently, these conditions are difficult to distinguish from lung infection, leading to missed diagnosis, inappropriate antibiosis, chemotherapy deferrals, and prolonged hospitalizations. Greater awareness and consensus definitions of LI and ATLP are therefore needed to improve care of this population.