A Dark Pigmented Spot in the Nasopharynx

Abstract

A man in his 60s with a history of hyperlipidemia, gout, and sleep apnea had a consultation for an incidental finding of a left torus tubarius, blackish, mucosal lesion noted during a health examination at a local clinic in July 2014. He had no nasal obstruction, nasal bleeding, or feeling of aural fullness. Fibroscopic evaluation revealed a black nevus-like lesion over the left torus tubarius, without surface necrosis or signs of bleeding when touched. Examination of the neck, nasal cavity, and larynx showed no remarkable findings. It was recommended that he receive laser excision of the lesion under endoscopy. During the surgery, the superficial lesion was found to be confined to the left torus tubarius, without invasion of the surrounding structures (Figure, A, arrowhead). The margins were clearly identified, and laser excision was performed smoothly with only minimal bleeding. The surgical specimen was a single black, soft-tissue fragment measuring 0.4 × 0.3 × 0.2 cm. Microscopy revealed small mixed serous and mucinous glands, normal respiratory epithelia with marked oncocytic cell changes, and abundant eosinophilic granular cytoplasm arranged in a tubular and microcystic pattern (Figure, B). Scattered brown pigments were noted in the cytoplasm of most oncocytic cells (Figure, C). There was no dyskeratosis. The brown pigment was negative for iron stain ( Figure, D) and HMB45 stain, but positive for Fontana Masson stain. Ki-67 staining revealed low proliferative index in the lesion. Some lymphocytic infiltration of the stroma was also noted.

Melanotic Oncocytic Metaplasia of the Nasopharynx: A Case Report With Review of Literature

“…1 Later on, the lesion was reported in Japan, Korea, Taiwan, and China. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] The exceptional geographical distribution of MOM may link its occurrence to genetic predisposition in East and Southeast Asia. Of all the literatures, 7 (46.7%) reports were from Japan, followed by Taiwan (20.0%) and China (13.3%).…”