J Korean Assoc Oral Maxillofac Surg.  2016 Feb;42(1):60-64. 10.5125/jkaoms.2016.42.1.60.

Neurilemmoma in the floor of the mouth: a case report

• Shim SK
• Myoung H

• KMID: 2189420
• DOI: http://doi.org/10.5125/jkaoms.2016.42.1.60

Abstract

Neurilemmomas are well-encapsulated, benign, slow-growing tumors originating from Schwann cells of the nerve sheath surrounding cranial, peripheral, or autonomic nerves. Intraoral neurilemmomas are relatively rare and have a wide variety of morphologic and radiologic features. This makes differential diagnosis difficult, and only histopathological features can lead to a definitive neurilemmoma diagnosis. In this report, we present the case of a 30-year-old woman whose chief complaint was a solitary, nodular mass on the right floor of the mouth. After computed tomography and magnetic resonance imaging, we performed an incisional biopsy that showed the typical characteristics of a neurilemmoma. The mass was removed completely through an intraoral surgical approach. Despite losing a portion of the lingual nerve, the patient did not complain of any specific discomfort. Wound healing was uneventful and there were no signs or symptoms of recurrence.

Keyword

Neurilemmoma; Sublingual gland; Case reports

MeSH Terms

Adult
Autonomic Pathways
Biopsy
Diagnosis
Diagnosis, Differential
Female
Humans
Lingual Nerve
Magnetic Resonance Imaging
Mouth*
Neurilemmoma*
Recurrence
Schwann Cells
Sublingual Gland
Wound Healing

Figure

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  Fig. 1 Preoperative intraoral clinical photograph.

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  Fig. 2 Computed tomography showing a heterogeneous enhancing lesion. A. Axial view. B. Coronal view. The artifact was seen through all cuts.

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  Fig. 3 T1-weighted magnetic resonance imaging showing a well-defined heterogeneous lesion. A. Axial view. B. Coronal view.

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  Fig. 4 T2-weighted magnetic resonance imaging showing a well-defined heterogeneous lesion. A. Axial view. B. Coronal view.

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  Fig. 5 Perioperative clinical photograph. A. The mass was removed through an intraoral approach. B. The mass was well-encapsulated and removed as a whole.

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  Fig. 6 Postoperative photograph of main mass. A. The mass was well-encapsulated and ovoid in shape. B. Upon dissection of the mass, many exophytic lobules were detected.

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  Fig. 7 Microscopic examination of the mass. A. Antoni B pattern with less cellularity, left. Antoni A pattern with well-organized, high cellularity, right (H&E staining, ×40). B. Streaming fascicles of spindle-shaped Schwann cells surround a central acellular, eosinophilic region of Verocay bodies (H&E staining, ×100). C. Magnification of the Antoni A area shows no evidence of cellular dysplasia in spite of high cellularity (H&E staining, ×100). D. Immunohistochemistry shows reactivity to S-100 protein (×100).

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