Laryngeal Amyloidosis Causing Hoarseness and Airway Obstruction

Amyloidosis constitutes a fraction of 1% of benign localized laryngeal tumors and may occasionally be associated with systemic disease. A chronic, insidious, progressive, recurrent disease characterized by hoarseness, dyspnea, and stridor, it is caused by extracellular deposition of insoluble, abnormal tissue injurious fibrils. Submucosal lesions occur frequently in the vestibular folds and ventricles, less commonly in the subglottis and aryepiglottic folds and least on the vocal folds. Apple green birefrigence under polarized light after Congo red staining, electron microscopic fibrillar structure, and a beta-pleated sheet structure observed by x-ray diffraction are confirmatory. Two presented cases add to the small literature review of similar patients. Case I was a 70-year-old man with severe hoarseness, incomplete glottic closure, ovoid concentric stenosis of the inferior glottis and subglottis, who initially was not diagnosed by several laryngologists and speech therapists. He required multiple microlaryngoscopic excisions and dilations. Because low dose radiation induces plasma cell apoptosis in other diseases, external beam radiation therapy (EBRT) was hypothesized to eliminate amyloidogenic plasma cells. Case 2 was a 46-year-old welder with progressive dyspnea for 2-3 years and hoarseness, voice loss, and stridor over 6-7 months. Masses caused airway obstruction of the anterior commissure, vestibular, and vocal folds, with extension to the subglottis. Two phonomicrosurgical CO2 laser-assisted resections relieved upper airway obstruction and restored voice. Conservative surgical intervention and long-term followup are essential. Further studies are needed to determine if a radiation dose response relationship exists to control laryngeal amyloidosis.