Usefulness of Preoperative Endobronchial Ultrasound for Airway Invasion around the Trachea: Esophageal Cancer and Thyroid Cancer

<i>Background:</i> It is important to confirm preoperative tracheobronchial invasion to enable the selection of the most appropriate treatment. <i>Objective:</i> This study was performed to compare the usefulness of computed tomography (CT), magnetic resonance image (MRI) and bronchoscopy by endobronchial ultrasonography (EBUS) for the assessment of invasion of thyroid or esophageal cancer in cases with suspected tracheobronchial invasion. <i>Methods:</i> In cases with suspected contact between the tumor and tracheobronchial wall, CT, MRI and EBUS indicated deformity of the tracheobronchial wall due to the adjacent mass. The final diagnosis was based on surgical and histological results, and/or clinical follow-up. <i>Results:</i> Fifty-four patients were included in this study. Based on the findings of CT, MRI and EBUS, invasion was suspected in 29, 28 and 25 patients, respectively. Seventeen patients did not undergo surgery based on the results of CT, MRI and bronchoscopy with EBUS. Final diagnosis was intact trachea or bronchial adventitia in 26 patients and invasion in 28 patients. The sensitivity and specificity of CT, MRI and EBUS for invasion were 59 and 56, 75 and 73, and 92 and 83%, respectively. The accuracy of EBUS was significantly greater than that of CT in the present study (p = 0.0011). The accuracy of EBUS was significantly different from that of CT and MRI in the surgically treated patients (p = 0.005 and p = 0.032, respectively). <i>Conclusion:</i> EBUS is the most useful technique for determining the depth and extent of tumor invasion into the airway wall. The combination of MRI and EBUS will contribute to surgical planning in patients with esophageal and thyroid cancer.