title: Case report of Mammary Analog Secretory Carcinoma of the parotid gland.
abstract: Mammary Analog Secretory Carcinoma (MASC) is a new entity of malignant salivary gland tumors that morphologically resembles mammary secretory carcinoma and carries the identical ETV6-NTRK3 fusion gene. We report our first case of MASC in Japan occurring in the parotid gland of a 37-year-old female patient with a t (12; 15) (p13; q25) translocation. Histologically, the tumor was composed of monomorphic cuboidal cells with low-grade vesicular nuclei and pale eosinophilic cytoplasm, and formed microcystic and tubular spaces with periodic acid-Schiff-positive secretion. Immunohistochemically, the tumor cells tested positive for cytokeratin, vimentin, and S-100 protein. MASC is a morphological mimicker of acinic cell carcinoma, but is a distinct neoplasm characterized by a specific chromosomal translocation. An accumulation of similar case studies is mandatory in order to clarify biological behaviors.
authors.affiliation: Department of Pathology, Miyagi Cancer Center, Natori City, Japan. sig-itoh@umin.ac.jp
authors.forename: Shigemi
authors.initials: S
authors.lastname: Ito
authors.forename: Eiichi
authors.initials: E
authors.lastname: Ishida
authors.forename: Alena
authors.initials: A
authors.lastname: Skalova
authors.forename: Kazuto
authors.initials: K
authors.lastname: Matsuura
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kumamoto
authors.forename: Ikuro
authors.initials: I
authors.lastname: Sato
mesh_terms: D000328:Adult; D002277:Carcinoma / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D010307:Parotid Neoplasms / Q000473:pathology* / Q000601:surgery; D016896:Treatment Outcome