著者

牧志 祥子 又吉 亮 宮本 昇 平野 惣大 仲宗根 敏幸 中村 博幸

出版者

社団法人 日本口腔外科学会

雑誌

日本口腔外科学会雑誌 (ISSN:00215163)

巻号頁・発行日

vol.67, no.3, pp.194-199, 2021

被引用文献数

1

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<p>Malignant peripheral nerve sheath tumors (MPNSTs) are very rare malignant neoplasia that arise from the peripheral nervous system and show nerve sheath differentiation. We report a case of primary malignant peripheral nerve sheath tumor of the mandibular gingiva.</p><p> A 53-year-old male was referred to our hospital presenting with a mass and pain in the mandibular gingiva. He had no appreciable disease and paralysis of the lower lip.</p><p> Computed tomography showed resorption of the mandible but no obvious lymph node metastasis.</p><p> Biopsy revealed a possible invasive unusual neuroectodermal tumor. Surgical resection was performed and the frozen section showed negative margins.</p><p> Histology revealed atypical spindle cells with clear chromatin and clear nucleolus which had proliferated and loosely infiltrated, but the cell boundaries were unclear. Immunohistochemical staining showed positive results for S-100 protein, p53, and vimentin, but negative results for pan-cytokeratin (AE1 / AE3), Melan A, and desmin. The Ki-67 labeling index was 10%. Accordingly, we diagnosed a low-grade peripheral nerve sheath tumor of the mandibular gingiva.</p><p> There were no signs of recurrence or metastasis at two years postoperatively. MPNSTs have poor prognoses and require careful follow-up.</p>