title: Mucoepidermoid carcinoma with spindle cell change: a low-grade lesion potentially mistaken for sarcomatoid dedifferentiation.
abstract: An unusual case of mucoepidermoid carcinoma (MEC) of intraoral minor salivary gland origin with spindled morphology was presented. A fascicular stream of bland spindle cells from typical MEC areas amounted to more than 70% of the tumor. Spindle population had features consistent with immunohistochemical and ultrastructural profiles of intermediate cells and lacked overexpression of p53 and cyclin D1. There was no difference in the Ki-67 index between two distinct components. Awareness of extensive spindle cell change replacing a significant portion of low-grade MEC is crucial to avoid an erroneous interpretation of dedifferentiated sarcomatoid transformation.
authors.affiliation: Department of Pathology, Tsurumi University School of Dental Medicine, 2-1-3 Tsurumi, Tsurumi-ku, Yokohama, Japan. ide-f@tsurumi-u.ac.jp
authors.forename: Fumio
authors.initials: F
authors.lastname: Ide
authors.forename: Kenji
authors.initials: K
authors.lastname: Mishima
authors.forename: Ichiro
authors.initials: I
authors.lastname: Saito
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D018277:Carcinoma, Mucoepidermoid / Q000175:diagnosis* / Q000378:metabolism / Q000601:surgery; D054337:Cell Dedifferentiation / Q000502:physiology; D002471:Cell Transformation, Neoplastic; D022083:Cytoplasmic Structures / Q000648:ultrastructure; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D019394:Ki-67 Antigen / Q000378:metabolism; D012468:Salivary Gland Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000601:surgery; D012470:Salivary Glands, Minor / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D012509:Sarcoma; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen