Supraglottic adenoid cystic carcinoma mimicking laryngeal amyloidosis: A case report

Abstract

Supraglottic adenoid cystic carcinoma (ACC) is extremely rare and may be misdiagnosed as laryngeal amyloidosis. The present report describes a case of supraglottic ACC, which went unrecognized until histopathological examination of the neoplasm 18 months after the first presentation. The present patient presented with progressive hoarseness for half a year and initially required partial resection. Following quick regional recurrence, the patient received a total laryngectomy while refusing radiotherapy. Adjuvant post-operational traditional Chinese medicine was accepted. Over 3 years' follow-up, there was no evidence of regional relapse or distant metastases. The present case is compared with a second case of supraglottic submucosal mass in which the signs, symptoms and examinations were similar to the first case, but that was diagnosed as laryngeal amyloidosis. Attention should be paid to submucosal masses in the larynx to prevent underlying malignancy and subsequent disease progression. Immunocytochemistry, such as p63 staining, is mandatory for making an early differential diagnosis of supraglottic ACC. Traditional Chinese medicine may be a useful adjuvant therapy for this rare disease.

Keywords: laryngeal amyloidosis; supraglottic adenoid cystic carcinoma.

Figure 1

(A) Fiber optic laryngoscopy images identifying chronic congestion of the bilateral vocal folds and swelling of the left ventricular fold. The mucosa of the bilateral pyriform fossa was soft and no neoplasm was observed (18 months prior to the first surgery). (B) No obvious change one week prior to the first surgery. (C) Computed tomography of the larynx showing asymmetry of the bilateral posterior structure, an enlarged laryngeal wall beside the left pyriform fossa and a soft-tissue mass with obscure margins involving the left ventricular fold, the anterior commissure and extending to the pyriform fossa.

Figure 2

(A) Fiber optic laryngoscopy at two days post-surgery. (B) Median power view showing the mixed tubular and cribriform pattern of ACC (original magnification, ×20). (C) Expression of p63 in ACC (original magnification, ×20). ACC, adenoid cystic carcinoma.

Figure 3

(A) Fiber optic laryngoscopy of laryngeal amyloidosis. (B) Computed tomography (CT) showing a mass in the right supraglottic region. (C) Paraffin-embedded, hematoxylin and eosin-stained tissue section showing extracellular, eosinophilic and amorphous amyloid (original magnification, ×40). (D) Paraffin-embedded, hematoxylin and eosin-stained tissue section under polarized light, with apple-green birefringence (original magnification, ×40).