Imaging Features of Pulmonary Leukemic Infiltration with Comparison of Lymphoid and Myeloid Leukemias

Abstract Purpose To describe the imaging findings of lung infiltration by leukemia and differential findings of lymphoid and myeloid leukemias. Materials and Methods Through a search of electronic medical records from 2005 to 2017, we identified 21 patients with pathologically proven lung involvement by leukemia. Concurrent CT findings were analyzed by two chest radiologists in consensus for ground glass or consolidative opacities, septal thickening, bronchovascular bundle thickening, pulmonary nodules, pulmonary masses, and hilar and mediastinal lymphadenopathy. Results There were 13 cases of lymphoid leukemias and 8 of myeloid leukemias. Nodules and masses were the most common imaging feature (n=13, 62%). Bronchovascular bundle thickening and hilar lymphadenopathy were exclusively seen in lymphoid leukemias (p=0.01 and p=0.006). Centrilobular nodules were also exclusively seen in 3 patients with chronic lymphocytic leukemia. Conclusion Lung infiltration by leukemia presents most commonly with nodules or masses, but interstitial abnormalities such as bronchovascular bundle thickening were seen as well. Radiologists should consider leukemic infiltration in the differential diagnosis for nodules, including centrilobular nodules, in these patients.