Long-Segment Malignant Tracheal Stenosis from Recurrent Medullary Thyroid Carcinoma Successfully Palliated with a Covered Self-Expanding Metallic Stent: A Case Report

Background: Medullary thyroid carcinoma (MTC) may rarely cause malignant central airway obstruction (MCAO) through locoregional tracheal invasion, requiring urgent multidisciplinary management. Case Presentation: A 58-year-old non-smoking woman with a history of MTC treated with total thyroidectomy and adjuvant radiotherapy presented with progressive exertional dyspnea, productive cough, intermittent mild stridor, and recurrent respiratory infections. She was tachycardic and tachypneic with preserved oxygen saturation on room air. Examination showed a firm, fixed mass in the thyroid bed region. Laboratory investigations revealed mild anemia and thrombocytosis. Computed tomography demonstrated approximately 5-cm long tracheal involvement with critical luminal narrowing, consistent with malignant tracheal stenosis due to suspected locoregional recurrence. Tracheal biopsy showed high-grade carcinoma considered clinically compatible with recurrence; immunohistochemistry and RET mutation testing were unavailable. The disease was deemed unresectable because of local invasion involving the trachea and carotid sheath. Case Discussion: In unresectable thyroid cancer–related MCAO, interventional bronchoscopy with airway stenting offers rapid restoration of airway patency and symptomatic palliation. Systemic targeted therapy was considered but was not available locally; therefore, urgent airway palliation was prioritized. A covered self-expanding metallic tracheobronchial stent (Ultraflex™, 16 × 60 mm; 45-mm covered segment) successfully traversed the stenotic segment. Conclusion: Covered metallic airway stenting provided meaningful improvement in breathing and phonation, representing an effective palliative option for long-segment unresectable malignant tracheal stenosis.