Display of esophageal entrance by injecting gas through the laryngoscopic biopsy channel in hypopharyngeal cancer

Abstract

To investigate the method displaying the hypopharynx and esophageal entrance under laryngoscopy to determine the invasion range of hypopharyngeal cancer. A total of 113 patients with hypopharyngeal cancer was enrolled in this study and they previously underwent conventional laryngoscopic and radiologic examinations. The esophageal entrance was exposed by injecting gas through the biopsy channel of laryngoscope. The invasion of esophageal entrance in hypopharyngeal cancers was evaluated by this method and compared with that evaluated with radiology. Conventional laryngoscopy was unable to evaluate appreciably esophageal entrance involvement in the 113 patients with hypopharyngeal cancer. After injecting gas through the laryngoscopic biopsy channel, the esophageal entrance was clearly displayed in 96.5% (109/113) patients, showing the presence (33 cases) and absence (76 cases) of esophageal entrance invasion. Imaging examinations only showed the invasion of the esophageal entrance in 25 patients of these patients,but did not in other 8 patients. Laryngoscopy with injecting gas through the biopsy channel was superior to radiological imaging examinations in determining the invasion of the esophageal entrance (χ² = 9.103, P = 0.003). Laryngoscopy with injecting gas through the biopsy channel is a useful method for determining the presence or absence of esophageal entrance invasion in hypopharyngeal cancer prior to surgery.