Carinal Squamous Cell Carcinoma Causing Progressive Central Airway Obstruction: CT, FDG PET/CT, Bronchoscopic Pre- and Post-Debulking, and Pathologic Correlation.

Primary tracheobronchial tumors are rare and are frequently diagnosed late because their presenting symptoms are nonspecific and may mimic more common respiratory conditions. We report a case of a 74-year-old man with a significant smoking history who presented with progressive dyspnea, cough, hemoptysis, and stridor, initially treated with multiple courses of antibiotics and corticosteroids, without improvement. Chest radiography was reportedly normal, but a contrast-enhanced CT demonstrated an endoluminal soft tissue mass centered at the distal trachea/carina with extension into the bilateral mainstem bronchi, causing near-complete obstruction of the left mainstem bronchus and moderate-to-severe narrowing of the right mainstem bronchus. Coronal FDG PET/CT demonstrated intense metabolic activity centered at the carina. Predebulking bronchoscopy confirmed a verrucous fungating carinal mass causing severe central airway compromise, whereas postdebulking bronchoscopy showed marked restoration of airway patency. Histopathologic evaluation established squamous cell carcinoma. This case highlights the diagnostic limitations of chest radiography and the essential role of CT, FDG PET/CT, and bronchoscopy in evaluating malignant central airway obstruction.