Schwannomas (or neurilemmomas) of the tongue are benign, usually solitary, encapsulated masses derived from Schwann cells. Clinical evidence indicates that schwannoma is painless and slow growing. In general, schwannoma is treated by surgical excision.
Here, we describe a case of schwannoma of the tongue, include a review of the literature from 1955 to 2016, and provide data on age, gender, location, presenting symptoms, size, and treatment methods.
Case presentation
A 71-year-old female patient presented with a swelling at the base of the tongue of unknown duration. Magnetic resonance images (MRI) showed a large well-circumscribed solid mass and no significant lymph node enlargement. The mass was excised without removing overlying mucosa.
Conclusions
The authors report a case of lingual schwannoma that was completely removed intraorally without preoperative biopsy. No sign or symptoms of recurrence were observed at 12 months postoperatively.
Keywords
SchwannomaNeurilemmomaTongue
Background
Around 25–40% of schwannomas occur in the head and neck region, and of these, 1–12% affect the intraoral area [1], most frequently the tongue or mouth floor [2]. Because of their rarity, intraoral schwannomas are not generally part of the differential diagnosis of tongue mass which includes squamous cell carcinoma, sarcoma, granular cell tumor, salivary gland tumor, schwannoma, leiomyoma, rhabdomyoma, hemangioma, lipoma, lymphangioma, dermoid cysts, and inflammatory lesions [3].
Clinically, schwannomas are benign, usually solitary, encapsulated masses that originate from Schwann cells without pain or ulceration.
Here, we report a case of schwannoma of the tongue base and review the literature. A Google search of the terms “schwannoma (neurilemmoma) of the tongue” and “lingual Schwannoma” was performed from 1955 to 2016. Age, gender, location (anterior, posterior, base, ventral), presenting symptoms, size, and treatment methods were extracted from case reports.
Case presentation
A 71-year-old female patient presented with a firm swelling at the base of her tongue of unknown duration that had progressively increased in size. Her only symptom was distortion of the tongue. Medical history taking revealed controlled hypertension (duration X years) and thyroid grand tumor. A well-encapsulated nodular mass was evident at physical examination, but without any neurologic symptom or lymphadenopathy in the submandibular area. The mass was 3 × 2 cm sized without ulceration (Fig. 1). Magnetic resonance imaging (MRI) depicted a solid, soft, heterogeneously enhanced lesion (Figs. 2 and 3). Complete surgical excision was conducted under general anesthesia without preoperative biopsy. Blunt dissection was performed without rupturing the mass or causing dehiscence of superficial mucosa. The mass was completely excised under mucosa (Fig. 4). It had been infiltrated by a branch of the lingual nerve, and a portion of the nerve had to be removed to achieve complete resection. On gross examination, the mass was grayish-yellow and well encapsulated with exophytic lobules (Fig. 5). Microscopically, the lesion was characterized by a mixture of Antoni type A and B tissue growth patterns with hyalinized vessel walls (Fig. 6). No sign or symptoms of recurrence were detected 12 months after surgery (Fig. 7).
Fig. 1
Preoperative intraoral photograph. The mass, which is located in the left tongue base, is covered by normal oral mucosa
Fig. 2
T1-weighted magnetic resonance image showing a well-defined heterogeneous lesion (white arrow). a Axial view. b Coronal view
Fig. 3
T2-weighted magnetic resonance image showing a well-defined heterogeneous lesion (white arrow). a Axial view. b Coronal view
Fig. 4
Perioperative clinical photographs. a The mass (white arrow). b The well-encapsulated mass is removed without adhesion (white arrow). c Photograph of the lesion through an overlying mucosal flap (white arrow). d Sutured state
Fig. 5
Gross anatomy. a Macroscopically, the excised specimen is nodular, soft, and grayish and had dimensions of 2.8 × 2.0 × 3.5 cm. The mass was attached to the lingual nerve (white arrow). b The cut surface of the mass has a pearly white appearance
Fig. 6
Microscopic examination. The mass is composed of Antoni A (black arrow) and Antoni B (black empty arrow) regions. a Antoni type A consists of closely packed Schwann cells arranged in rows with palisading and elongated nuclei (white arrow). b Antoni type B of hyalinized vessels in a myxoid background (white arrow) (H&E, ×100)
Fig. 7
Intraoral photograph obtained at 12 months postoperatively showing no sign of recurrence
A review of the literature over the past 61 years that showed 84 cases, including the present case, has been reported (Table 1). Lingual schwannoma may arise at any age between 7 and 77 and shows no sex predilection (44 males and 40 females) [4, 5]. Despite the fact that it originates from nerve tissue, lingual schwannoma is usually painless.
Table 1
Patients and tumor characteristics of tongue schwannomas
MRI magnetic resonance images, CT computed tomography
In 51 cases, the only presenting symptom was an enlarging lump. Other symptoms were dysphagia (15 cases), pain (or discomfort, 10 cases), dysphonia (6 cases), voice change (5 cases), paresthesia (3 cases), snoring (2 cases), bleeding (2 cases), ulceration (2 cases), and abscess (1 case). Masses were located in any part of the tongue. Average size at removal was 2.4 cm (range, 0.3–8.5 cm), and all were treated by transoral excision except 3 cases. The submandibular approach was used in 2 cases and lip splint and mandibulectomy in 1 case. In all three of these cases, masses were located in posterolateral bases.
Discussion
Although the etiology of schwannoma is not clear, it is known to be derived from nerve sheath Schwann cells, which surround cranial, peripheral, and autonomic nerves [6, 7]. The head and neck are rather common location of this neoplasm. Intraoral schwannomas mainly arise from the tongue, followed by the palate, mouth floor, buccal mucosa, gingiva, lip, and vestibule [8, 9], though the tongue is most commonly involved [10]. The lesion is slow growing, and thus, its onset is usually long before presentation. Lingual schwannoma shows no age or gender predisposition [11]. Usually, it is presented as a painless lump in any part of the tongue of average size 2.4 cm. However, when the mass exceeds 3.0 cm, dysphagia, pain (or discomfort), dysphonia, and voice change are usually presented (Table 1).
Computed tomography (CT) usually shows well-defined homologous lesions. When a heterogeneous lesion is observed by CT, malignant change may be suspected [12]. However, MRI is superior to CT at depicting lingual schwannoma, as it is not degraded by dental artifacts that plague CT in the intraoral area. Lesion signals are isointense versus muscle on T1-weighted images, but hyperintense on T2-weighted images [13]. MRI also allows mass size to be accurately measured and mass localization in relation to other structures. Characteristically, these tumors usually appear to be smooth and well demarcated and do not invade the surrounding structures.
In our case, MRI ruled out the possibility of malignancy and invasion. Enoz et al. [14] reported a malignant transformation rate for head and neck schwannoma of 8–10%. In general, schwannoma does not undergo malignant transformation [15, 16]. However, several cases of malignant transformation of head and neck schwannomas have been reported, although only one involved the tongue [17]. One malignant transformation was evident in our patient.
Histologically, all schwannomas are encapsulated, and beneath capsules, two main patterns are observed, that is, Antoni type A, which is highly cellular and is composed of elongated Schwann cells, which exhibit a palisading nuclear pattern, and Antoni type B, which is also composed of elongated Schwann cells, but cells are arranged in a less dense myxoid manner and are more disorganized than Antoni type A (Fig. 6).
Schwannomas are usually treated by surgical excision with involved originating nerve [18]. In the literature, transoral excision is the most common approach used (Table 1), although some other approaches have been reported to produce success results, such as the submandibular, which is adopted to address lingual schwannoma of the posterolateral base. More recently, CO2 laser excision has also been used to treat base of tongue Schwannomas [5, 17]. On the other hand, if a mass is located at the posterolateral base, is inaccessible via the mouth, and has a size >4.0 cm, open techniques, such as the submandibular or lip split approach, are used [2, 4, 19]. Schwannomas are not responsive to radiotherapy [9], and incomplete surgical excision may result in recurrence, although recurrence is uncommon after complete surgical excision [20]. Because masses are encapsulated, their complete removal is straightforward. In our patient, overlying mucosa was preserved to minimize postoperative complications and promote rapid healing without inflammation, and during follow-up, she reported little inconvenience.
Conclusions
Lingual schwannoma is a relatively rare tumor of the head and neck and may occur anywhere in the tongue. At presentation, the majority of patients complain an asymptomatic mass and slight ulceration. Transoral resection preserving overlying mucosa allowed us to remove the tumor in a manner that precluded recurrence and prevented tongue dysfunction.
Declarations
Acknowledgements
This work was supported by the research grant of the Chungbuk National University Hospital in 2016.
Authors’ contributions
All the authors contributed to the work described in the paper, and all take responsibility for it. All authors read and approved the final manuscript.
Competing interests
The authors declare that they have no competing interests.
Consent for publication
Written informed consent was obtained from the patient for publication of this case report and accompanying images.
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.
Authors’ Affiliations
(1)
Department of Oral and Maxillofacial Surgery, College of Medicine and Medical Research Institute, Chungbuk National University
References
Harada H, Omura K, Maeda A (2001) A massive pleomorphic adenoma of the submandibular salivary gland accompanied by neurilemomas of the neck misdiagnosed as a malignant tumor: report of case. J Oral Maxillofac Surg 59:931–935View ArticlePubMedGoogle Scholar
de Bree R, Westerveld G, Smeele L (2000) Submandibular approach for excision of a large schwannoma in the base of the tongue. Eur Arch Otorhinolaryngol 257:283–286View ArticlePubMedGoogle Scholar
Nelson W, Chuprevich T, Galbraith D (1988) Enlarging tongue mass. J Oral Maxillofac Surg 56:224–227View ArticleGoogle Scholar
George N, Wagh M, Balgopal P, Gupta A, Sukumaran R, Sebastian P (2014) Schwannoma base tongue: case report and review of literature. Gulf J Oncolog 16:94–100Google Scholar
Lira RB, Filho G, Carvalho GB, Pinto CA, Kowalski LP (2013) Lingual schwannoma: case report and review of the literature. Acta Otorhinolaryngol Ital 33:137–140PubMedPubMed CentralGoogle Scholar
Arda H, Akdogan O, Arda N, Sarikaya Y (2003) An unusual site for an intraoral schwannoma: a case report. Am J Otolaryngol 24:348–50View ArticlePubMedGoogle Scholar
Hsu Y, Hwang C, Hsu R, Kuo F, Chien C (2006) Schwannoma (neurilemmoma) of the tongue. Acta Otolaryngol 126:861–865View ArticlePubMedGoogle Scholar
Tsushima F, Sawai T, Kayamori K, Okada N, Omura K (2012) Schwannoma in the floor of the mouth: a case report and clinicopathological studies of 10 cases in the oral region. J Oral Maxillofac Surg Med Pathol 24:175–179View ArticleGoogle Scholar
Gallo W, Moss M, Shapiro D, Gaul J (1977) Neurilemmoma: review of the literature and report of five cases. J Oral Surg 35:235–236PubMedGoogle Scholar
Lopez J, Ballistin C (1993) Intraoral schwannoma: a clinicopathologic and immunohistochemical study of nine cases. Arch Anat Cytol Pathol 41:18–23PubMedGoogle Scholar
Bhola N, Jadhav A, Borle R, Khemka G, Bhutekar U, Kumar S (2014) Schwannoma of the tongue in a paediatric patient: a case report and 20-year review. Case Rep Dent. 2014;2014:780762. doi:https://doi.org/10.1155/2014/780762
Cohen L, Schwartz A, Rockoff S (1986) Benign schwannomas: pathologic basis for CT inhomogeneities. AJR 147:141–143View ArticlePubMedGoogle Scholar
La'porte S, Juttla J, Lingam R (2011) Imaging the floor of the mouth and the sublingual space. Radiographics 31:1215–1230View ArticlePubMedGoogle Scholar
Dreher A, Gutmann R, Grevers G (1997) Extracranial schwannoma of the ENT region. Review of the literature with a case report of benign schwannoma of the base of the tongue. HNO 45:468–471PubMedGoogle Scholar
Naik S, Goutham M, Ravishankara S, Appaji M (2012) Sublingual schwannoma: a rare clinical entity reported in a hypothyroid female. Int J Head Neck Surg 3:33–39View ArticleGoogle Scholar
Sawhney R, Carron M, Mathog R (2008) Tongue base schwannoma: report, review, and unique surgical approach. Am J Otolaryngol 29:119–122View ArticlePubMedGoogle Scholar
AL-Alawi Y, Kolethekkat A, Saparamadu P, Al Badaai Y (2014) Sublingual gland schwannoma: a rare case at an unusual site. Oman Med J 29. doi:https://doi.org/10.5001/omj.2014.41
Mercantini E, Mopper C (1959) Neurilemmoma of the tongue. AMA 79:542–544Google Scholar
Cameron I (1959) A case of neurilemmoma (schwannoma) of the tongue. Oral Surg Oral Med Oral Pathol 12:1464–1467View ArticlePubMedGoogle Scholar
Sharan R, Akhtar M (1978) Neurilemmoma of tongue. J Indian Med Assoc 71:290–291PubMedGoogle Scholar
Akimoto Y, Yamamoto H, Nishmura H, Komiya M, Kaneko K (1987) Neurilemmoma in the oral cavity. J Nihon Univ Sch Dent 29:203–205View ArticlePubMedGoogle Scholar
Sira C, Ng K, Chia T, Kulkarni M (1988) Atypical neurilemmoma of the tongue: report of two cases. Dent Update 29:83–85Google Scholar
Flickinger F, Lozano R, Yuh W, Sachs M (1989) Neurilemmoma of the tongue: MR finding. J Comput Assist Tomgr 13:886–888View ArticleGoogle Scholar
Talmi Y, Gal R, Finkelstein Y, Shvilli V, Zohar Y (1991) Pathologic quiz case 1: benign schwannoma of tongue. Arch Otolaryngol Head Neck Surg 117:926–928View ArticlePubMedGoogle Scholar
Gallesio C, Berrone S (1992) Schwannoma located in the tongue: a clinical case report. Minerva Somatologica 41:583–590Google Scholar
Haring J (1994) Case #10. Neurilemmoma. RDH 14:12–12Google Scholar
Nakayama H, Gobara R, Shimamot F, Kajihara H (1996) Ancient schwannoma of the oral floor and ventricular portion of the tongue: a case report and review of literature. Jpn J ClinOncol 26:185–188Google Scholar
Spandow O, Frgerlund M, Bergmark L, Boquist L (1999) Clinical and histopathological features of a large parapharyngeal neurilemmoma located at the tongue. ORL J Otorhinolaryngol Relat Spec 61:25–30View ArticlePubMedGoogle Scholar
Pfeifle R, Baur D, Paulino A, Helmen J (2001) Schwannoma of the tongue: report of 2 cases. J Oral Maxillofac Surg 59:802–804View ArticlePubMedGoogle Scholar
Cinar F, Cinar S, Harman G (2004) Schwannoma of the tip of the tongue in a child. Plast Reconstr Surg 114:1657–1658PubMedGoogle Scholar
Bassichis B, McMlay J (2004) Pedunculated neurilemmoma of the tongue base. Otolarygol Head Neck Surg 130:639–641View ArticleGoogle Scholar
Nakasato T, Kamada Y, Ehara S, Miura Y (2005) Multilobular neurilemmoma of the tongue in the child. AJNR Am J Neuroradiol 26:421–423PubMedGoogle Scholar
Lopez-Jornet P, Bermejo-Fenoll A (2005) Neurilemmoma of the tongue. Oral Oncology EXTRA 41:154–157View ArticleGoogle Scholar
Vafiadis M, Fiska A, Panopoulou M, Assimakopoulo D (2005) A clinical case report of a schwannoma on the tip of tongue. B-ENT 1:201–204PubMedGoogle Scholar
Bansal R, Trivedi P, Patel S (2005) Schwannoma of the tongue. Oral Oncology EXTRA 41:15–17View ArticleGoogle Scholar
Ying Y, Zimmer L, Myers E (2006) Base of tongue schwannoma: a case report. Laryngoscope 116:1284–1287View ArticlePubMedGoogle Scholar
Mehrzad H, Persaud R, Papadimitriou N, Kaniyur S, Mochloilis G (2006) Schwannoma of tongue base treated with transoral carbon dioxide laser. Lasers Med Sci 21:235–237View ArticlePubMedGoogle Scholar
Batra K, Rai A, Chaudhary N, Topno S (2007) Two cases of neurilemmoma of the tongue. ENT-Ear Nose Throat J 86:679–681Google Scholar
Ballesteros F, Vilaseca I, Blanch J, Gaspa A, Bernal-Sprekelsen M (2007) Base of tongue neurilemmoma: excision by transoral laser microsurgery. Acta Otolaryngol 127:1005–1007View ArticlePubMedGoogle Scholar
Sethi D, Sethi A, Nigam S, Agarwal A (2008) Schwannoma of oral tongue: a rare benign neoplasm. IHANS Vol. 3, No. 1. 8496Google Scholar
Pereira L, Pereira P, dos Santos JP, Reis Filho V, Dominguete PR, Pereira AA (2008) Lingual schwannoma involving the posterior lateral border of the tongue in a young individual: case report. J Clin Pediatr Dent 33:59–62View ArticlePubMedGoogle Scholar
Gupta P, Garg A, Dhingra K, Jain D, Kohli K, Khurana N (2009) Schwannoma tongue: a rare entity. ANZ J Surg 79:93–94View ArticlePubMedGoogle Scholar
Mardanpour K, Rahbar M (2009) Lingual schwannoma: a case report. IRCMJ 11:454–456Google Scholar
Karaca C, Habesoglu T, Naiboglu B, Habesoglu M, Oysu C, Egeli E, Tosun I (2010) Schwannoma of the tongue in a child. Am J Otolaryngol 31:46–48View ArticlePubMedGoogle Scholar
Cigdem T, Tulay E, Baris N, Mehmet H, Cagatay O, Erol E, Iikay T (2010) Schwannoma of the tongue in a child. Am J Otolaryngol Head and Neck Med and Surg 31:46–48Google Scholar
Jeffcoat B, Pitman K, Brown A, Baliga M (2010) Schwannoma of the oral tongue. Laryngoscope 120(Suppl 4):S154View ArticlePubMedGoogle Scholar
Naidu G, Sinha S (2010) Schwannoma of the tongue: an unusual presentation in a child. IJDR 21:457–459PubMedGoogle Scholar
Lukšić I, Müller D, Virag M, Manojlović S, Ostović K (2011) Schwannoma of the tongue in a child. J Craniomaxillofac Surg 39:441–444View ArticlePubMedGoogle Scholar
Batra U, Usha G, Gogia A (2011) Anesthetic management of schwannoma of the base of the tongue. JOACP 27:241–243Google Scholar
