Inflammatory Myofibroblastic Tumor of Lung

Comments:
The alveolar architecture is largely intact in early stages of inflammatory pseudotumor. In later stages, the native lung architecture is completely effaced by collagen deposition. This image shows a trapped bronchiole (lower left) and a couple of alveolar airspaces (top), demonstrating the locally destructive nature of this lesion. Abundant plasmacytic infiltrate, characteristic of this lesion, can be appreciated in this field.