Schwannoma in the sublingual space

Diagnosis and management of hypoglossal nerve-derived schwannoma in the floor of mouth: a case series

BACKGROUND

Schwannomas or neurilemmomas are well-encapsulated, benign, solitary, and slow-growing tumors that originate from Schwann cells of the nerve sheath. Extracranial schwannoma is reported to have a relatively high incidence in the tongue while an extremely low incidence in the floor of mouth. In the current study, we presented the first case series of hypoglossal nerve-derived schwannoma in the floor of mouth in Asia.

METHODS

A retrospective study of 9 surgical cases of hypoglossal nerve-derived schwannoma in the floor of mouth was performed. The patient and tumor characteristics were evaluated by physical, radiological and pathological examination. Details of operation and complications were also recorded.

RESULTS

Hypoglossal nerve-derived schwannoma in the floor of mouth showed a well-defined boundary with a firm texture, smooth surface and good mobility on palpation. The median maximum diameter of the tumors was 4.3 cm (range 2.8-7.0 cm). The median operative time and bleeding volumes were 89.4 min (range 47-180 min) and 99.2 mL (range 15-200 mL), respectively. All cases received complete surgical excision.

CONCLUSION

In this study, we presented the diagnosis and management of hypoglossal nerve-derived schwannoma in the floor of mouth for the first time in Asia. The study provided us with a recommendation for consideration of the diagnosis of hypoglossal schwannoma when a patient presents with a mass in the floor of mouth.

Auricle Schwannoma: Presentation of a Rare Case and Review of Existing Literature

Schwannomas are extremely rare over auricle. Despite the extensive somatogenic neural innervations of the pinna, schwannomas are never amongst the differentials for a benign auricular mass. Previously published articles have all agreed on the rarity of this lesion occurring over the auricle. However, none of the articles have tackled and extensively reviewed the auricle schwannomas (AS) as an individual entity. The article aim to review previously published cases of AS along with an illustrative case, and provide a better insight regarding demographic, clinicopathological and immunohistochemical features of this neural tumor in a rare site. A systemic review of English literature was performed after using a sensitive search strategy involving three different databases (PubMed, Google Scholar and Embase). A total of nine cases were included. They mostly presented in young adults as a slow growing tumor (mean duration: 3.17 years) and showed a slightly higher male predominance (male/female ratio 1.25:1). They were mostly located over lateral surface (66.67%) with a predilection for left ear (77.78%). Conventional histological variant has only been reported. Complete surgical excision was performed for all the cases without any reports of recurrence or malignant transformation. AS present as a solitary, painless, firm and well-encapsulated lesion, mostly over the lateral auricle surface. Preoperative clinical diagnosis is difficult and radiological investigations do not hold much importance. FNAC is inconclusive and diagnosis mandates histopathologic examination. The nerve of tumor origin is difficult to precisely identify. Complete surgical excision is the treatment of choice. Post-operative prognosis is excellent.

Palatal Schwannoma: An Analysis of 45 Literature Reports and of an Illustrative Case

Introduction  Schwannomas are benign tumors originating from differentiated Schwann cells. Being the least common intraoral neoplasm of neural origin, it is rarely seen in the palate. The literature lacks an extensive review of intraoral schwannoma confined to the palate.

Objective  To review previously reported cases of palatal schwannoma along with an illustrative case, and to provide a better insight regarding clinicopathological and radiological features of this neural tumor in a rare intraoral site.

Data Synthesis  We present a case of palatal schwannoma in a 16-year-old female. An additional 45 cases were identified in 2 medical database searches (PubMed and Google Scholar) published from the year 1985 onwards, and from 13 countries, in the 5 continents. The ages of the patients ranged from 3 to 84 years old. Palatal schwannoma showed a slight predilection to females, with a male/female ratio of ∼ 1:1.81. Hard palate involvement is almost twice greater than soft palate involvement. Surgical excision was employed in almost all of the cases, and recurrence was reported only once.

Conclusion  Palatal schwannomas, although rare, have been reported both over the hard and the soft palate. They mostly present as a painless, firm, well-encapsulated, slow-growing solitary lesion over the lateral palatal aspect.

Imaging can add to suspicion and can delineate a differential diagnosis, but the diagnosis is confirmed by pathological examination. Fine-needle aspiration cytology (FNAC) is almost always inconclusive. Immunohistochemistry can assist in confirming a diagnosis, but is more important to rule out close differentials. Complete surgical excision is the treatment of choice, and recurrence or malignant transformation are extremely rare.

A Case of Schwannoma of the Submandibular Region

Background:

We herein described a rare case of schwannoma of the hypoglossal nerve in the submandibular region with diagnostic imaging and histopathological findings.

Case Report:

A 31-years-old woman has had a palpable firm, rubbery, freely mobile mass in the submandibular region. Of imaging, MR images showed homogeneous isointensity on T1-weighted imaging (T1-WI), heterogeneous hypointensity on T2-WI, heterogeneous hyperintensity on short T1 inversion recovery (STIR), and heterogeneous enhancement on contrast-enhanced T1-WI. A clear capsule was observed on the margin and showed hypointense on T2-WI. Dynamic MRI showed heterogeneous gradual increased enhancement. The uptake of contrast medium was regionally slow. Diagnostic imaging using CT and MRI was suspected of salivary gland tumor or neurogenic tumor. In consideration of imaging diagnosis, a pleomorphic adenoma or a schwannoma was suspected. Final diagnosis was confirmed on the basis of histopathological finding and intraoperative findings.

Conclusion:

1. Histopathologic examination is inevitable, because MR findings are not specific.

2. Schwannomas were said to have specific MRI properties, including specific signs (split-fat sign, fascicular sign, target sign). However, they are not always observed.

3. This case confirmed the differential diagnosis on the basis of the intraoperative finding that the tumor was continuous with the hypoglossal nerve.

Collet-Sicard Syndrome With Hypoglossal Nerve Schwannoma: A Case Report

Collet-Sicard syndrome is a rare syndrome that involves paralysis of 9th to 12th cranial nerves. We report an uncommon case of schwannoma of the hypoglossal nerve in a 39-year-old woman presented with slurred speech, hoarse voice, and swallowing difficulty. Physical examination revealed decreased gag reflex on the right side, decreased laryngeal elevation, tongue deviation to the right side, and weakness of right trapezius muscle. MRI revealed a mass lesion in the right parapharyngeal space below the jugular foramen. The tumor was surgically removed. It was confirmed as hypoglossal nerve schwannoma via pathologic examination. Videofluoroscopic swallowing study revealed aspiration of liquid food and severe bolus retention in the vallecula and piriform sinus. Laryngoscopy revealed right vocal cord palsy. Electrodiagnostic study revealed paralysis of the right 11th cranial nerve. In summary, we report an uncommon case of schwannoma of the hypoglossal nerve with 9th to 12th cranial nerve palsy presenting as Collet-Sicard syndrome.

Schwannoma of the Submandibular Gland: A Rare Case Report

Schwannoma is a slow growing, benign, encapsulated tumour of Schwann cells, which form myelin in peripheral nerves. It is the most common tumour of peripheral nerve, also known as neurilemoma or neurimoma. Schawannomas of head and neck area is common and may arise from peripheral, central or autonomic nerve but Salivary gland schwannomas are rare extracranial forms. We report a rare case of schawannoma of submandibular gland which presented with painless swelling in submandibular region, treated by total excision of submandibular gland. There was no postoperative nerve deficit or recurrence within 9 months of follow up.

Imaging findings of benign peripheral nerve sheath tumor in jaw

OBJECTIVE

The aim of this study was to investigate the imaging characteristics of peripheral nerve sheath tumors (PNSTs) in the jaw.

STUDY DESIGN

Imaging studies of 6 patients were retrospectively reviewed. Conventional radiography, computed tomography, and magnetic resonance imaging were performed in all patients.

RESULTS

A fusiform lesion continuous with the nerve was observed in 2 cases, with the tumor arising within the inferior alveolar canal. In the other 4 cases, with the tumor arising outside the canal, the tumor had protruded and eroded into the bone. Protrusion was also present in 1 of the 2 cases, with the tumor arising within the canal. A target or fascicular sign was observed each in 1 case.

CONCLUSIONS

A fusiform lesion continuous with the nerve and a target or fascicular sign was only present in a few cases. The PNSTs, however, showed a tendency to protrude into the bone.

Rare occurrence of intraosseous schwannoma in a young child, its review and its pathogenesis

Schwannoma is a benign, encapsulated, perineural tumor that arises from the Schwann cells. Approximately 25% of the reported cases originate from the head and neck region. Of these, approximately 1–12% occurs intraorally. The intrabony lesion accounts for less than 1% of the central neoplasms. We report a rare case of intraosseous schwannoma in an 8-year-old male patient characteristically originating from the mental nerve. Radiographic examination followed by histopathological evaluation was further confirmed by immunohistochemical markers, S-100 protein, and GFAP that stained intensely positive for the tumor. Thus, confirming the diagnosis of intraosseous schwannoma.

Imaging the floor of the mouth and the sublingual space

A wide range of pathologic processes may involve the floor of the mouth, the part of the oral cavity that is located beneath the tongue. They include lesions that arise uniquely in this location (eg, ranula, submandibular duct obstruction) as well as various malignancies, inflammatory processes, and vascular abnormalities that may also occur elsewhere in the head and neck. Some lesions that arise in superficial tissues such as the mucosa may be easily diagnosed at physical examination. However, computed tomography, magnetic resonance imaging, or ultrasonography may be necessary for a reliable assessment of lesion extension to deeper structures. In such cases, knowledge of the complex muscular, vascular, glandular, ductal, and neural anatomy of the region is important for accurate diagnosis and treatment planning. Familiarity with the radiologic imaging appearances of the floor of the mouth and recognition of anatomic landmarks such as the mylohyoid and hyoglossus muscles are especially useful for localizing disease within this region.

Imaging findings of neurogenic tumours in the head and neck region

OBJECTIVE

The aim of this study was to describe the CT, MRI and ultrasonography findings of five cases of neurogenic tumours in the head and neck region.

METHODS

Five neurogenic tumours were analysed with respect to their CT value, the presence of cystic change, target sign, lobulation, connection to the nerve and vascularity.

RESULTS

The contrast-enhanced CT (ECT) of the schwannomas demonstrated either a mass with low enhancement (two out of three cases), which reflected the predominant Antoni B components, or a mass with cystic changes, which was an Antoni A-based schwannoma displaying cystic changes (one out of three cases). On MRI, all tumours showed homogeneous and isointense signals for muscle on T₁ weighted images (T₁ WIs). T₂ weighted images (T₂ WIs) and gadolinium (Gd)-enhanced T₁ WIs demonstrated target sign in both schwannomas. Ultrasound examination showed a well-defined, ovoid or round hypoechoic mass. The direct connection to the nerve was demonstrated in two of the five cases. Lobulation was observed in only one of the five cases and cystic changes were observed in one of the five cases. In all of the cases, no vascularity was seen in power Doppler images (PDIs) obtained percutaneously.

CONCLUSIONS

Low-enhanced areas on ECTs can be specific for schwannomas, which suggests the predominance of Antoni B components. The target sign on T₂ WIs and Gd-enhanced T₁ WIs can be specific, which can be used to differentiate the two different components (Antoni A and Antoni B). The direct connection to the nerve can be a specific finding for neurogenic tumours; however, at present the sensitivity is 40%.

Hypoglossal schwannoma of parapharyngeal space: an unusual case report

Schwannomas are benign tumor of the schwann cells. These are common in eighth, tenth cranial nerves and parasympathetic chain. Hypoglossal schwannomas are rare. Among the hypoglossal schwannomas the intracranial and dumb-bell shaped schwannomas are frequent but extra cranial hypoglossal schwannomas are rare. We describe a parapharyngeal hypoglossal schwannoma in a 25 years female presenting as slow growing mass in right side of the neck.

Palatal schwannoma in an elderly woman

Schwannoma also known as neurilemmoma is a benign tumour derived from schwann cells and is relatively rare in occurrence. Only 1% of the schwannomas in the head and neck region occur at intra-oral sites. Schwannomas usually occur during the third or fourth decades of life and the tongue is the most common intra-oral site. A case of intra-oral schwannoma in a 70-year-old female in the region of hard palate is described which is extremely rare.

Schwannoma causing resorption of zygomatic arch

Schwannoma (also known as neurilemmoma, peripheral glioma and peripheral nerve sheath tumor) is a common, histologically distinctive, benign, usually encapsulated, peripheral nerve tumor of Schwann cell origin. Schwannomas can appear anywhere in the body, but are more frequently reported in the head and neck with an incidence of 25-48% in maxillofacial region. Resorption of bones due to schwannoma is rarely noticed in maxillofacial region. We hereby present a case report of schwannoma in a 35-year-old female, causing resorption of zygomatic arch along with review of literature.

Multiple schwannomas in the oral floor: case report

We present a case of multiple schwannomas of the oral floor in a 62-year-old man, which met the diagnostic criteria of schwannomatosis.

A unique case of a sublingual-space schwannoma arising from the mylohyoid nerve

We describe a unique case of a sublingual-space schwannoma presenting as a painless, 3 x 2-cm enlarging mass in the oral cavity of a 63-year-old man. Computed tomography demonstrated a distinct, well-encapsulated mass in the right side of the floor of the mouth. Findings on fine-needle aspiration cytology were consistent with a pleomorphic adenoma. Transoral excision was performed. Intraoperatively, the mass appeared to involve the nerve to the mylohyoid muscle. Upon removal, the gross tumor measured 4.4 x 3.5 x 2.5 cm. On microscopic examination, the spindle-cell neoplasm was found to be consistent with a schwannoma. Schwannomas of the sublingual space are exceedingly rare. Moreover, to the best of our knowledge, this case represents the first published occurrence of a schwannoma that arose from the mylohyoid nerve.

Schwannoma with secondary erosion of mandible: case report with a review of the literature

Schwannoma (neurilemmoma) is a common, histologically distinctive, benign, usually encapsulated, peripheral nerve tumour of Schwann cell origin. We report a case of schwannoma arising from soft tissue near the mandible. A 53-year-old female presented at our department with painless swelling of lingual mucosa of the mandible. The first molar was extracted 20 months before. Panoramic radiograph showed a suspected residual cyst. It was impossible to determine prior to surgery whether this was a peripheral nerve sheath tumour. The lesion was completely removed; the tumour appears to have originated in soft tissue and caused secondary erosion of the mandible.