Carcinoid tumor of the middle ear: a case report and review of literature.

Carcinoid tumors of the middle ear are very rare. Here we describe a 37-year-old man with multiple recurrent carcinoid tumor of the right middle ear. The CT demonstrated the recurrent mass that filled the tympanum and mastoid with osteolytic invasion, and the tumor was removed by surgery. The pathological findings showed the tumor cells, without necrosis and mitotic activity, had round, oval, or slightly irregular nuclei and finely-dispersed chromatin, arranged in cords, nests, and glandular structures. They were strongly positive for synaptophysin and CD56, but were negative for S-100 and chromogranin A. Ki-67 proliferation activity was low (<2%). With a review of the literature, the clinical, pathological characteristics and treatment modalities of this rare tumor are discussed.