Pulmonary Leukemic Infiltration: Radiologic Patterns and Clinical Correlation in Myeloid and Lymphoid Disease

Abstract

Pulmonary leukemic infiltration (PLI) is a rare but significant thoracic manifestation of leukemia. It is often underdiagnosed due to its nonspecific presentation and overlapping features with infection or drug-related lung injury. Differentiating PLI from infectious pneumonia or drug-induced lung injury is crucial for appropriate treatment and prognostication. Awareness of PLI's radiologic patterns, especially in patients with high leukemic burden or relapse, facilitates timely diagnosis and management. PLI presents with diverse imaging features such as ground-glass opacities (GGO), septal thickening, consolidation, and centrilobular nodules. Acute myeloid leukemia (AML) frequently shows GGO- and consolidation-dominant patterns, while lymphoid leukemias may present with nodular infiltrates and pleural effusions. HRCT-pathology correlation studies demonstrate that these patterns reflect direct leukemic cell infiltration. Incorporating HRCT findings into clinical assessment significantly improves diagnostic accuracy. This case-based review synthesizes findings from key radiologic and pathologic studies focusing on CT and high-resolution CT (HRCT) features of PLI with reference to relevant literature and imaging findings across different leukemia subtypes.