title: Atypical carcinoid (neuroendocrine carcinoma) of the gingiva: counterpart of a laryngeal tumor.
abstract: Intraoral localization of neuroendocrine carcinoma, usually called Merkel cell carcinoma, is extremely rare. A case of neuroendocrine carcinoma that was a counterpart of laryngeal neuroendocrine carcinoma but was not a Merkel cell carcinoma, occurring at the mandibular gingiva in a 69-year-old Japanese man, is described. The tumor formed a cauliflower-like mass, measuring 20 x 20 mm, with a small area of necrosis. A computed tomography image showed metastasis in the right submandibular lymph node. Histopathologically, the tumor was composed of immature, small round cells that formed anastomosing trabecular nests. Few mitotic and no necrotic features were observed in the nests. Immunohistochemical studies showed positive staining for chromogranin, synaptophysin and neuron-specific enolase in the tumor nests. We diagnosed it as an atypical carcinoid (neuroendocrine carcinoma), a counterpart to the same type of tumor occurring in the larynx. The present case is an extremely rare case of neuroendocrine carcinoma without the feature of Merkel cell carcinoma arising from the gingiva.
authors.affiliation: Department of Oral Pathology, School of Dentistry, Health Sciences University of Hokkaido, Hokkaido, Japan. yoshi-ab@hoku-iryo-u.ac.jp
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Abiko
authors.forename: Ikuko
authors.initials: I
authors.lastname: Ogawa
authors.forename: Yufo
authors.initials: Y
authors.lastname: Hattori
authors.forename: Kaoru
authors.initials: K
authors.lastname: Kusano
authors.forename: Michiko
authors.initials: M
authors.lastname: Nishimura
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Ohuchi
authors.forename: Uichi
authors.initials: U
authors.lastname: Abe
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Shibata
authors.forename: Shinji
authors.initials: S
authors.lastname: Matsuda
authors.forename: Takashi
authors.initials: T
authors.lastname: Takata
authors.forename: Tohru
authors.initials: T
authors.lastname: Kaku
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis; D002276:Carcinoid Tumor / Q000737:chemistry / Q000556:secondary* / Q000601:surgery; D053379:Chromogranin A / Q000032:analysis; D005887:Gingival Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000601:surgery; D006801:Humans; D007822:Laryngeal Neoplasms / Q000473:pathology*; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D010751:Phosphopyruvate Hydratase / Q000032:analysis; D016708:Synaptophysin / Q000032:analysis; D014057:Tomography, X-Ray Computed
chemical_list: D014408:Biomarkers, Tumor; D053379:Chromogranin A; D016708:Synaptophysin; D010751:Phosphopyruvate Hydratase