LEUKEMIC PULMONARY INFILTRATION: A RARE COMPLICATION OF ACUTE LYMPHOBLASTIC LEUKEMIA

Abstract

TOPIC: Pulmonary Manifestations of Systemic Disease TYPE: Fellow Case Reports INTRODUCTION: We report a rare case of pulmonary leukemic infiltration that posed a diagnostic dilemma. CASE PRESENTATION: A 61 year old female presented with weeks of weakness, nausea, vomiting, diarrhea. Initial laboratory evaluation revealed hyperleukocytosis of >100,000 cells/microliter with 86% blasts and thrombocytopenia. A bone marrow biopsy revealed B cell type ALL. Hydroxyurea was initiated for cytoreduction. On hospitalization day 3 she developed hypoxemia requiring 2-3 L supplemental oxygen. Chest radiograph revealed mild patchy airspace opacities. Extensive non-invasive infectious work up was negative. Over next week she developed worsening dyspnea and hypoxemia, with near tandem progression of radiographic airspace disease, despite antibiotics and stabilization of blood count. CT chest revealed diffuse patchy ground glass opacities, small pleural effusion and adjacent atelectasis. Bronchoscopy showed bloody secretions, with BAL differential showing abundant atypical cells with irregular nuclear contours, fine chromatin and prominent nucleoli, consistent with lymphoblastic leukemic blast cells. Concern was for pulmonary leukemic infiltration vs DAH with peripheral blood blast spillage. High dose corticosteroids were initiated. Her clinical condition deteriorated requiring endotracheal intubation and ICU admission. Due to her critically ill status, she was treated dose reduced, moderate intensity Cyclophosphamide and Vincristine chemotherapy. A repeat BAL revealed similar findings of ~30% blasts on differential. Subsequently her respiratory status improved, she was extubated and discharged on low supplemental oxygen. Bone marrow restaging 4 weeks after initial treatment showed persistent B acute lymphoblastic leukemia in the bone marrow. Her oncology team is planning for mini-HOP induction with Larson consolidation. DISCUSSION: Thoracic involvement of leukemia is varied, from leukemic pulmonary infiltration, hyperleukocytopathic reaction, leukostasis, DAH, lymphadenopathy, pleural effusion etc. CT findings of leukemic pulmonary infiltration are nonspecific, however leukemic cells have a tendency to involve the perilymphatic interstitium, producing smooth or nodular thickening of the bronchovascular bundles and interlobular septa. Nodules are also common and may be peribronchovascular, centrilobular, or random in distribution. Ground-glass and consolidative opacities are less common, predominately in peribronchial regions, by infiltration of the parenchyma adjacent to the perilymphatic interstitium. Accurate diagnosis usually requires bronchoalveolar lavage or lung biopsy to rule out other common etiologies. Response to primary chemotherapy usually depends on primary leukemia and patient's clinical status, but usually portends a poor prognosis. CONCLUSIONS: Clinicians need to thoroughly investigate pulmonary infiltrates in a leukemic patient in order to ensure appropriate therapy. REFERENCE #1: Shroff, G. S., et al (2019). Leukemic involvement in the thorax. Radiographics, 39(1), 44-61. DISCLOSURES: No relevant relationships by Jyotirmayee Lenka, source=Web Response No relevant relationships by Naman Sharma, source=Web Response