Nerve sheath myxoma (Neurothekeoma) of the gingiva, A case report and review of the literature

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原文題目(出處)： Nerve sheath myxoma (Neurothekeoma) of the gingiva, A case report and review of the literature

原文作者姓名： Safadi RA, Hellstein JW, Diab MM, Hammad HM

通訊作者學校： Department of Oral Surgery and Medicine, Faculty of Dentistry, Jordan University of Science and Technology, Irbid 22110, Jordan

報告者姓名(組別)： Intern E 組 沈昕叡

報告日期： 99.12.7

內文：

Introduction

 Nerve sheath myxoma (neurothekeoma) 是一種罕見的來自周邊神經良性軟組 織瘤.

 通常會出現在頭頸部的真皮或是皮下組織，較少出現在口腔內.

 A computer assisted PubMed search revealed only 23 reported intraoral cases of NSM.

 有報告指出的病例有從新生兒到73歲的病患.

 在22case中，女性男性佔的比例是13:9.

Lesion的最大直徑範圍大約從0.5cm~3.0cm.

 在口內最常出現的位置在舌頭，接下來依序是buccal mucosa, palate, lower lip, and retromolar pad.

 This study reports the first case of NSM (neurothekeoma) that occurred on the marginal gingiva simulating an epulis.

Case Report

 一位32歲的女性到the dental clinic of Prince Basma Hospital.

 她的主訴是在她右上正中門牙唇側的marginal gingiva出現一個不會痛，但有 逐漸變大的一個腫塊，大約六個月左右.

 口外的醫師幫她做了切除的手術，並下診斷為‘‘epulis’’.

 組織切片檢查可以發現腫塊有完整邊界，呈現lobular的排列.

 The lobules 細胞排列較疏鬆，包含clustered thin spindled and stellate cells mixed with variable amounts of myxoid matrix.

Hematoxylin and eosin stain of neurothekeoma section (10×).

Notice the well demarcation of the lesion from superficial submucosa.

 Short thick collagen bundles as well as mast cells were interspersed within the lobules.

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Hematoxylin and eosin stain of neurothekeoma sections (20×).

Note the presence of thick, short collagen bundles and focal myxoid areas. Note the presence of epithelioid/stellate cells.

 免疫組織化學染色法去分析S100 protein, neuron specific

enolase (NSE), epithelial membrane antigen (EMA), glial fibrillary acidic protein (GFAP), CD68 (a macrophage marker), smooth muscle actin (SMA) and HMB45 (a melanocyte marker).

 Below shows clusters of S100 positive, wavy, thin spindled cells with scattered mast cells, sometimes with close proximity to neural cells.

Immunohistochemical stain of S100 protein counterstained with hematoxylin, using horse radish peroxidase technique (40 ×).Note the positivity of thin spindled neural cells in short fascicles

presented as brown/darkly stained cytoplasm. Note the presence of a mast cell in the rounded rectangle.

 根據組織學和免疫組織化學分析結果，這個案例診斷為 mixed type 的 nerve sheath myxoma.

Discussion

 由黏液基質的量來分，nerve sheath myxoma可以分成myxoid(classical), mixed and cellular types.

 The case reported in this study is of the mixed type showing moderate amounts of myxoid stroma.

 NSM 的細胞來源還有些爭議，目前有比較多的理論認為來源是由增生 的許旺細胞或是其他周邊神經細胞來的.

 一 般 來 說 ， 來源 自 許 旺細 胞 在 免疫 組 織 化學 分 析 上 S100和 NSE是 positive，EMA是negative.

 The immunohistochemical profile of the case presented in this study is of S100 positivity, weak positivity for NSE, negativity for GFAP, EMA, CD68, SMA and HMB45 confirming nerve sheath origin from Schwann cells.

 The clinical differential diagnoses of NSM presenting as an epulis include chronic hyperplastic gingivitis, focal fibrous hyperplasia, pyogenic

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granuloma, peripheral ossifying fibroma, peripheral giant cell granuloma, giant cell fibroma and peripheral odontogenic fibroma.

 Nerve Sheath Myxoma

Histopathologic differential diagnosis

Neural

True neuroma

Myxoid neurofibroma

Non-neural

 Local excision is the treatment of choice for NSM.

 No recurrence after local excision has been reported for oral cases.

題號 題目

1

(A) Buccal mucosa (B) Tougue

(C) Marginal gingiva (D) Palate

答案(B ) 出處：Oral& Maxillofacial Pathology, Second Edition,p.456

題號 題目

2

(A) HMB45 (B) SMA (C) S100 (D) CD68

答案( C) 出處：Oral& Maxillofacial Pathology, Second Edition,pg.456