Figure 2.

Histopathologic evaluation of resected tracheal tissue. (A) Axial sections of tracheal segment showing luminal stenosis and peritracheal expansion of connective tissue. (B) Low-power image of the tracheal segment marked by ∗ in (A) demonstrating both luminal and peritracheal expansion by collagenous connective tissue (blue staining elements) on the Masson trichrome stain (magnification ×10). (C) In some areas, the mucosal layer was ulcerated and replaced by granulation tissue (hematoxylin and eosin, magnification ×200). (D) In other regions, the mucosal lining consisted of squamous metaplastic cells (hematoxylin and eosin, magnification ×200).