Clinical characteristics of laryngeal versus nonlaryngeal amyloidosis

Objectives/Hypothesis Amyloidosis represents a heterogeneous group of disorders marked by abnormal protein formation and deposition. Laryngeal amyloidosis is rare and classically thought to remain isolated with little risk of systemic involvement or associated malignancy. This study sought to further characterize differences in clinical characteristics between patients with laryngeal and nonlaryngeal amyloidosis. Study Design Retrospective case‐control study. Methods The Stanford Translational Research Integrated Database Environment was searched to identify patients with biopsy‐confirmed laryngeal amyloidosis and patients with amyloidosis without laryngeal involvement on endoscopy. Mann‐Whitney U and χ2 tests were used for statistical analysis. Results Of 865 patients treated for amyloidosis between 1996 and 2016, 22 (2.5%) patients with biopsy‐proven laryngeal amyloidosis were identified. An additional 22 patients with amyloidosis of a different organ and negative laryngoscopy—and therefore without laryngeal amyloidosis—were identified as controls. Compared to these controls with nonlaryngeal amyloidosis, patients with laryngeal amyloidosis were younger (mean age 52.8 years vs. 68.4 years, P < .0006), and 18% had additional organ involvement. Immunoglobulin light‐chain amyloidosis was the most common subtype in both groups of patients. Eighty‐six percent of patients with laryngeal amyloidosis required surgical excision, and of these patients, over 30% required multiple excisions. Conclusions There is a significant rate (18%) of multiorgan involvement in patients with laryngeal amyloidosis, which contradicts conventional concepts that this is an isolated disorder. This finding could have a significant impact on the evaluation and management of patients with laryngeal amyloidosis. Level of Evidence 3b. Laryngoscope, 128:670–674, 2018