Solitary Extramedullary Plasmacytoma of the Apex of Arytenoid: Endoscopic, CT, and Pathologic Findings

Abstract

Extramedullary plasmacytoma (EMP) is a rare plasma cell neoplasm that occurs mainly in the soft tissues of head and neck region, with the paranasal sinuses, nasal cavity and nasopharynx being the most common sites. Solitary EMP of the larynx is very rare but increasingly reported recently. Common sites of involvement in larynx in the order of frequency are the epiglottis, ventricles, vocal folds and ventricular folds. We report an extremely rare case of solitary EMP involving in the apex of arytenoids that was successfully treated by only surgical excision. Because solitary EMP of the apex of artytenoids is extremely rare, it should be included in the differential diagnosis for laryngeal mass. Also, solitary, small, pedunculated and localized EMP of the larynx could be completely removed by laryngeal microsurgery.

Keywords: Arytenoid; Extramedullary plasmacytoma; Surgical excision.

Fig. 1

Laryngeal examination revealed a mass clearly demarcated, localized in the apex of left arytenoid. The lesion was a reddish, polypoid growth.

Fig. 2

Computerized tomography of the neck revealed a well demarcated, minimally enhancing, 1.5×1.0×1.2 cm sized mass in the left arytenoid region.

Fig. 3

Histopathology revealed a dense monoclonal infiltrate of plasma cells with eccentrically situated nuclei with mild degree of nuclear polymorphism (A: ×200, B: ×400).

Fig. 4

Immunohistochemistry was done for kappa (A) and lambda light chains (B) and was positive for lambda chains, which confirmed the monoclonal nature of the plasma cells (×200).