Neural tumors of the oral cavity. A review of the spectrum of benign and malignant oral tumors of the oral cavity and jaws

Solitary intraosseous neurofibroma in the mandible mimicking a cystic lesion: A case report and review of literature

BACKGROUND

Neurofibromas are benign tumors of a neurogenic origin. If these tumors occur without any other signs of neurofibromatosis, they are classified as isolated neurofibromas. Neurofibromas in the oral cavity mostly occur within soft tissues, indicating that solitary intraosseous neurofibromas in the mandible are rare. Due to the absence of specific clinical manifestations, early diagnosis and treatment of these tumors are difficult to achieve.

CASE SUMMARY

A 37-year-old female patient visited our hospital due to numbness and swelling of the gums in the right lower molar area that had persisted for half a month. The patient's overall condition and intraoral examination revealed no significant abnormalities. She was initially diagnosed with a cystic lesion in the right mandible. However, after a more thorough examination, the final pathological diagnosis was confirmed to be neurofibroma. Complete tumor resection and partial removal of the right inferior alveolar nerve were performed. As of writing this report, there have been no signs of tumor recurrence for nine months following the surgery.

CONCLUSION

This case report discusses the key features that are useful for differentiating solitary intraosseous neurofibromas from other cystic lesions.

Pediatric schwannoma of the tongue: A case report and review of literature

BACKGROUND

Neurogenic tumors account for about ten percent of all tumors of childhood, and benign tumor originating from Schwann cells is rare in peripheral nerves. Schwannoma of the tongue is quite rare in children.

CASE SUMMARY

We present the case of an 8-year-old male with schwannoma in the anterolateral tongue. The mass was slow-growing for one year with no pain and discomfort. He underwent transoral mass excision under general anesthesia. Gross examination revealed a smooth surfaced, 17 mm × 14 mm × 7 mm sized, encapsulated nodule with a clear resection margin. Schwannoma of the tongue was confirmed by the pathological exam. He reported no motor or sensory change, such as dysgeusia or paresthesia, or phonation difficulty during postoperative 12 mo follow-up.

CONCLUSION

Schwannoma of the tongue is a rare benign neoplasm in childhood. If a painless firm mass is encountered in the tongue of a child, solid tumors like schwannoma should be considered in the differential diagnosis.

Schwannoma originating in the soft palate: A case report

Introduction and importance

Schwannomas are relatively uncommon, benign, slow-growing neoplasms, which are derived from schwann cells that can arise from any cranial, peripheral, or autonomic nerves. The involvement of the palate is a rare presentation and hardly reported in the literature.

Case presentation

Here, we report the case of a 39-year-old woman with a history of a foreign body sensation in the throat and difficult swallowing.

Clinical findings and investigations

Oral examination showed a smooth, non-tender, right-sided, soft palate mass. Computed tomography (CT) scan revealed a well-defined, non-enhancing, homogenous pedunculated soft tissue mass arising from the posterior edge of the right side of the soft palate.

Interventions and outcome

The mass was excised completely under local anesthesia in the clinical setting using a CO₂ surgical laser. The mass was sent for histologic analysis, which confirmed the diagnosis of a benign schwannoma.

Conclusion

Eventually, upon follow-up at six months post excision, no evidence of recurrence was detected.

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A 39-year-old woman presented with a two-month history of right sided soft palate mass causing difficult swallowing.

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The mass was completely excised in a clinical setting under local anesthesia using a CO2 surgical laser.

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Histopathologic analysis confirmed the diagnosis of a benign soft palate Schwannoma.

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After six months post excision, no evidence of recurrence was detected.

Pathological Diversity in Schwannomas of the Orofacial Region

Schwannoma is a slow-growing, encapsulated benign tumor of the neuroectodermal origin arising from the perineural Schwann cells. This study aims to elucidate the clinicoradiographical and histopathological features of orofacial schwannomas through a case series of seven cases. The patients' aged ranged from 13 to 45 years, with a male predilection in the ratio of 5:2. One intraosseous case presented as a radiolucent lesion. All the cases exhibited Antoni A and Antoni B type of microscopic patterns in varying amounts. One case of ancient schwannoma showed degenerative features. The tumor cells showed diffuse positive immunohistochemical reaction for S-100 protein. Our study suggests that intraosseous schwannoma should be considered in the differential diagnosis of the intraosseous jaw lesions. Histopathologically, it is important to recognize the findings of ancient schwannoma and to avoid misdiagnosing it as a malignant lesion.

Solitary Neurofibroma of the Hard Palate: A Case Report and Literature Review

Patient: Female, 24-year-old

Final Diagnosis: Neurofibroma

Symptoms: Bulging of the hard palate

Medication: —

Clinical Procedure: —

Specialty: Dentistry • Oncology

Maxillary schwannoma - A case report of a rare tumor

Schwannoma or neurilemmoma is a neurogenic tumor. Intraoral schwannoma is rare and intraosseous schwannoma involving maxilla is even rare. We present one such rare case of maxillary sinus schwannoma extending to the nasal cavity, infratemporal fossa in a 22-year-old male. Wide excision of the lesion with subtotal maxillectomy of the right side was done using Weber–Fergusson approach. The patient made a good postoperative recovery. The relevant literature on the presentation, radiology, and management of schwannoma of maxillary sinus is discussed.

Solitary Neurofibroma of the Soft Palate: A Rare Entity

The solitary neurofibroma is a benign tumor of neuronal origin uncommonly reported in the oral cavity. The possible association of this neoplasia with systemic pathologies, such as von Recklinghausen's disease and multiple endocrine neoplasia, makes its diagnosis fundamental. Solitary isolated neurofibroma of the soft palate not associated with von Recklinghausen's disease is an unusual tumor and probably only four cases have been reported in English literature previously. To the best of our knowledge, our case of soft palate neurofibroma in 17-year-old male represents the fifth reported in English literature, for which complete surgical excision was achieved with uneventful healing.

Tongue Schwannoma: A Clinicopathologic Study of 19 Cases

Schwannomas commonly occur in the head and neck but infrequently involve the oral cavity and rarely affect the tongue. The clinical and pathologic features of 19 cases of schwannoma arising in the tongue were analyzed. There were 13 males and 6 females ranging in age from 12 to 82 years (mean 34 years; median 29 years). The majority of tumors presented as an asymptomatic mass localized to the anterior two-thirds of the tongue. Histologically, 18 schwannomas exhibited characteristic Antoni A and B areas with the former pattern predominating. One tumor was composed exclusively of cellular Antoni A tissue and was classified as a cellular schwannoma. Tumor encapsulation was variable with nearly half of the lesions lacking a well-defined fibrous capsule. All were strongly and diffusely positive for S-100 protein. No recurrences were observed on clinical follow-up. Schwannoma of the tongue, although rare, should be separated from other types of lingual nerve sheath proliferations and tumors.

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.

Subgemmal Neurogenous Plaque: A Clinical and Pathologic Review With Comparison to Common Head and Neck Neural Tumors

Objective

In humans, subgemmal neurogenous plaques (SNPs) are normally found associated with taste buds. On histology, SNP may be mistaken for a neural neoplasm. The objective of this study was to correctly differentiate SNP among head and neck neural lesions and provide clinical and pathologic information that may assist in avoiding misdiagnosis. To our knowledge, this is the first study to provide an estimate of the degree of overdiagnoses of mucosal lesions in the head and neck mucosal area.

Study design

Retrospective pathology and chart review.

Methods

All cases of head and neck mucosal neural lesions only in the mucosa of the oral cavity, oropharynx, or larynx from the pathology archives of a single urban tertiary care center between 3/2000 and 6/2017 were obtained. The pathologic and clinical data were reviewed.

Results

Twenty-six cases were identified: 9 neuromas, 9 neurofibromas, 2 ganglioneuromas and 6 cases of hyperplastic subepithelial nerve bundles. The mean greatest dimension of SNPs was 2.0 mm (range 1-3 mm) and most were subjacent to taste buds (13 cases). The 20 cases of SNP involved 15 women and 5 men. Their median age was 60 years (range 30-85 years). Clinical data were available in 19 cases. The most common presenting complaint was of a painless lesion (8 patients).

Conclusions

This review confirmed the rarity of true neural neoplasms in the head and neck mucosa and estimates the risk of their over diagnosis given the possible diagnostic confusion with SNP.

Sporadic Neurofibroma of the Tongue Unassociated with Neurofibromatosis Type I: A Clinicopathologic Study of Ten Cases

Neurofibromas rarely occur within the oral cavity and infrequently involve the tongue. The majority of lingual neurofibromas arise in patients affected by neurofibromatosis type 1 (NF1). Neurofibromas of the tongue unassociated with this disorder are exceedingly uncommon. The clinical and pathologic features of 10 cases of sporadic lingual neurofibromas, unassociated with NF1, were evaluated. The patients included six females and four males ranging in age from 30 to 69 years (mean 59 years; median 63 years). An asymptomatic or slowly enlarging lingual mass was the most common clinical presentation. None of the patients were documented to have NF1. Histologically, the tumors were unencapsulated and situated beneath an intact squamous mucosa. The tumors are comprised of spindle cells with wavy nuclei within a collagenous to myxoid stroma. One tumor was characterized by a plexiform growth pattern. The lesional cells were positive for S-100 protein. Clinical follow up, available for all patients, showed no recurrences and no subsequent development of additional clinical manifestations of NF1. Lingual neurofibromas should be distinguished from other peripheral nerve sheath tumors that can affect this anatomic site. This series of cases confirms that sporadic neurofibromas of the tongue may be rarely encountered in patients having no other features of NF1.

Plexiform Schwannoma of the Tongue in a Pediatric Patient with Neurofibromatosis Type 2: A Case Report and Review of Literature

Introduction

Plexiform schwannoma is a rare variant of schwannoma that accounts for only 5% of all schwannomas. Herein, we present a rare case of plexiform schwannoma of the tongue in a pediatric patient with neurofibromatosis type 2 (NF2).

Case Presentation

A 13-year-old female presented with a growing left-sided tongue mass. The patient has a past medical history of NF2. The tongue mass was excised and histopathological examination revealed a spindle cell tumor with multinodular growth pattern, with Verocay bodies' formation. Tumor cells were strongly positive for S-100 protein and negative for smooth muscle actin (SMA), and EMA highlighted perineural fibroblasts surrounding tumor nodules. These findings were diagnostic of plexiform schwannoma.

Conclusion

Plexiform schwannoma of the tongue is an extremely rare tumor seen in patients with NF2. Clinical examination and histopathological evaluation are important for diagnosis of plexiform schwannoma.

Neuromastoma of the hard palate mucosa in an Australian green tree frog (Litoria caerulea)

A hard palate mass was surgically removed from an Australian green tree frog (Litoria caerulea) and examined pathologically. The tumor consisted of sheets of small cells arranged in a tubular structure and cords or rosettes with fibrovascular stroma. Immunohistochemically, neoplastic cells were diffusely positive for cytokeratin and neuron-specific enolase and partially positive for S-100 and doublecortin. These findings indicate that the tumor originated from the neuroectodermal tissue. Based on these findings, the tumor was classified as a neuromastoma (neuroepithelioma). Sensory cells located in the hard palate of the frog were considered to be the origin of the tumor. The frog died after going through 3 surgeries and experiencing difficulties closing its mouth.

Anterior Midline Glossotomy Approach for Large Schwannoma of the Tongue: Case Report

Schwannoma corresponds to a benign neurogenic tumor, derived from neural crest cells. It accounts for approximately 5% of all benign soft tissue tumors. These are the most common cause of peripheral nerve neoplasms of the oral cavity and oropharynx representing 1%. Isolated or solitary neurofibromas of the oral cavity usually involve the tongue or the labial mucosa. They appear as soft, painless, slow-growing masses that are tender to depression or palpation. The case of a 40-year-old woman is studied because of the presence of painless swelling, slow, and progressive growth of the oral language. Complete removal of the lesion was performed and primary closure was performed. It had a satisfactory evolution, maintaining adequate sensory and sensory mobility and innervation.

Large Solitary Neurofibroma of Face in a Paediatric Patient

Neurofibroma is a rare, benign, neurogenic tumour which may present as multiple lesions as a part of neurofibromatosis syndrome or as a solitary mass. This paper reports a case of large solitary neurofibroma of face in a young female patient. Clinical presentation, imaging characteristics and management of the pathology has been described in detail. The paper also reviews English literature for similar cases.

Intraoral neurilemmoma of mental nerve mimicking as traumatic fibroma: An unusual presentation - A case report and literature review

Neurilemmoma, neurinoma or schwannoma is a benign tumor of neurogenic origin, arising from the myelin sheath of a neuron. Head and neck region accounts for 25%-48% of these tumors reported till date. On the contrary, intraoral sites form only 1% of the cases accounted. Although a few cases of intraoral neurilemoma of mental nerve has been reported in English literature, none has been reported to arise from the terminal fibers of the mental nerve. In this particular article, we present a case were the tumor was noted in the lower labial mucosa.

Schwannoma of the tongue

Schwannoma, neurilemmoma or neurinoma is a rare, benign nerve sheath neoplasm composed of Schwann cells. It is usually solitary, slow growing and asymptomatic. Approximately 1-12% of the tumours occur intraorally with the tongue being the most common location. We report a rare case of lingual schwannoma in a 20-year-old female patient involving the tip of the tongue, which was slow growing and asymptomatic. For diagnosis histopathological examination and also immunohistochemistry testing were carried out to confirm the nature of tissue fragments. The treatment was complete surgical excision.

Oral Neurothekeoma of the Right Buccal Mucosa

Oral neurothekeoma or nerve sheath myxoma is a rare benign oral tumour of nerve sheath origin. Historically, this tumour has been subclassified as myxoid (classic), mixed, or the cellular type, depending on the amount of myxoid stroma and cellularity. We present a case of oral neurothekeoma (mixed type) of the buccal mucosa. The tumour was completely excised. No recurrence was detected in the last 3 years after local excision.

Schwannoma (Neurilemmoma) on the Base of the Tongue: A Rare Clinical Case

Patient: Female, 20

Final Diagnosis: Schwannoma of the tongue

Symptoms: Dysarthria • dysphagia

Medication: —

Clinical Procedure: Excision of the mass via trans-oral approach

Specialty: Surgery

Neurilemmoma of Retromolar Region in the Oral Cavity

Neurilemmoma also known as schwannoma is benign nerve sheath tumor rarely occurring in the oral cavity. Only 1% of all extracranial schwannomas show that intraoral occurrence with tongue is the commonest site and retromolar region is the least common site. It presents as encapsulated, slow growing, solitary, smooth-surfaced, usually asymptomatic tumor. We report a case of 70-year-old male with well-defined mass on left retromolar region which was painless and slow growing. Diagnosis is made by histological examination and immunohistochemistry analysis to confirm the neural tissue origin of the lesion. The treatment is complete surgical excision of the lesion without recurrence.

Sublingual Gland Schwannoma: A Rare Case at an Unusual Site

Intraoral schwannoma is a rare entity. Tongue has been reported as the most common oral site. Those involving salivary glands are unusual and parotid gland is the usual site. Literature search revealed only one case of schwannoma involving the sublingual gland. Hence, this is a presentation of another case of sublingual gland schwannoma with a review of literature, in a young female of 21 years old.

Ancient neurilemmoma: A rare oral tumor

Neurilemmomas are benign tumors of neural origin composed of Schwann cell proliferation in characteristic patterns. Ancient neurilemmomas are usually longstanding growths that exhibit degenerative features that could be mistaken for malignancy. They are extremely rare in the oral cavity and present in older individuals of long duration. The authors report a case of ancient neurilemmoma in a young patient with short duration of growth. This unique case presented with remarkable histopathological features with respect to vascularity and atypia associated with degenerative change. It is essential to not mistake these features as malignant transformation so as to avoid radical procedures.

Giant intraosseous schwannoma of scapula: a rare case report and review of the literature

Bony schwannoma is a rare benign tumor derived from schwann cells of nerve fibers in the bone. It accounts for less than 1% of bony benign tumor, and prone to occur in the sacrum and mandible, occurrence in scapula is very rare. Here we report a 42-year-old woman with the chief complaint of pain in the left scapula. Imaging examination showed a giant, irregular, swelling lesion with distinct border involving the left scapula, extending into the left shoulder glenoid and pressing the surrounding soft tissues. Needle biopsy showed that the tumor was composed of spindle cells with S-100 protein positive, mimicking a benign neurogenic tumor. Then a complete excision was performed by removing the tumor and the surrounding tissues including partial left shoulder glenoid. Histologically, Antoni type A areas were the predominant microscopic pattern with occasional alternation by Antoni type B areas. Immunohistochemistry found that the neoplastic cells were scatteredly positive for S-100 protein. All these features suggest a diagnosis of an intraosseous schwannoma of the left scapula. Follow-up of the patient for ten months found no recurrence or sign of other tumors following complete tumor resection without any adjuvant therapy. In conclusion, this case of giant intraosseous schwannoma of the scapula is a rare benign bony tumor, and its diagnosis combined with clinical, imaging and pre-operative needle biopsy is important to guide further therapy, and avoid overtreatment.

Treatment of a rare ganglioneuroma with resection and reconstruction of the mandible: a case report and literature review

Ganglioneuromas are rare neuroblastic tumors that develop from the neural crests of the sympathetic nervous system. Because ganglioneuromas of the mandible have been infrequent, they do not have a standardized management protocol. As of 2000, only 5 cases had been reported. Ganglioneuromas are unique tumors that can undergo histologic maturation from a malignancy to a benign variant. We present the case of a 15-year-old boy with a ganglioneuroma of the mandible and the results of surgical management, including immediate reconstruction with a free fibula microvascular flap.

Intraoral schwannoma in retromolar region

Schwannomas of the intra oral region are relatively uncommon; these are benign nerve sheath tumors that arise from schwann cells of the neural sheath. They are solitary, slow-growing, smooth-surfaced, usually asymptomatic, and encapsulated tumors, about 25% of all schwannomas are located in the head and neck, but only 1% show intraoral origin. We are contributing a report of 24 years old woman with slow progressive swelling over the right retromolar region. Magnetic resonance imaging presented a well defined mass over the right retromolar area measuring 19 × 19 mm(2) and fine needle aspiration cytology revealed that it was a tumor mass of neurogenic origin. Diagnosis was confirmed by excisional histological identification of Antoni A areas with marked palisading of nuclei. Although these rare entities of oral cavity are routinely not encountered in practice, they should be added in differential diagnosis of intraoral tumors.

Unusual solitary neurofibroma on the lower lip of a child

Neurofibromas (NF) are benign tumors with involvement of the peripheral nerve, which is not frequently located in the oral cavity, and especially, extraordinary rarity on lower lip of a child. This report describes a case of a NF on lower lip in a 12-year-old Brazilian child. NF consists of a wide variety of cell types, including Schwann cells, perineurial cells, and fibroblasts. Due to cellular heterogeneity, several hypotheses have been proposed to explain the histogenesis of this lesion. One of them, it support an origin of Schwannian, while others emphasize the participation of both Schwann cells and perineural cells. Excisional biopsy was performed to establish definitive diagnosis. Microscopically, the lesion was composed of interlacing bundles of elongated cells with wavy nuclei and small nerve fibers. Immunohistopathologic assessment showed cells positive for S-100, confirming the diagnosis of NF. No recurrence was observed after 1-year follow-up. Pediatric dentists must have a thorough knowledge of this unusual lesion.

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.

Intraoral nerve sheath myxoma: case report and systematic review of the literature

BACKGROUND

Oral nerve sheath myxoma (NSM) is an uncommon benign neoplasm with Schwann-cell origin, which is frequently mistaken for neurothekeoma. We report a case of NSM on the buccal mucosa in a 42-year-old woman. This case is compared with previously reported cases and a systematic review is performed.

METHODS AND RESULTS

We conducted a case report and systematic review of oral cases considered true NSMs. A literature search was performed using PubMed, Lilacs, Scielo, Cochrane, SciVerse Scopus, Web of Science, and Embase electronic database. Twenty-five cases of oral NSM were included in the systematic review.

CONCLUSION

Oral NSM is rare and may represent a diagnostic challenge for pathologists. To confirm the diagnosis of NSM, the evaluation of S-100 protein expression or other neural marker is essential. The use of the terms NSM and neurothekeoma as synonymous or as variants of the same tumor should be avoided, because they are clearly distinct lesions.

Schwannoma of the cheek: clinical case and literature review

INTRODUCTION

Schwannoma is a relatively uncommon benign tumor that apparently originates from Schwann cells of peripheral nerves. The most common intraoral site is the tongue followed by the palate, floor of mouth, buccal mucosa, lips and the jaws. The preoperative diagnosis is often difficult, and in the majority of cases, the diagnosis can only be made during surgery and by histological study. The immunohistochemistry reveals that the schwannoma cells test positive for S-100 protein.

CASE REPORT

The authors report here a case of an intraoral schwannoma situated in the cheek, treated by complete surgical excision. In the present case the schwannoma presented as a slow growing, circumscribed swelling without any particular features to distinguish it from other benign soft-tissue lesions. The final diagnosis was established based on the clinical, histopathologic and immunohistochemical findings.

CONCLUSION

The presence of schwannoma calls for the careful search for nerve tumors in other parts of the body, although in most cases none may be found. The differentiation of schwannoma from neurofibroma is essential, because an apparently solitary neurofibroma may be a manifestation of neurofibromatosis.

Unusual intramaxillary plexiform schwannoma

BACKGROUND

Neoplasms of peripheral nerve in the head and neck region are of common occurrence, but origin in the oral and para-oral tissues is uncommon and they rarely occur centrally within the jaws. Schwannoma is a benign neoplasm originating from the neural sheath of peripheral soft tissues, but its occurrence within the jaw bones is most unusual. Plexiform schwannoma is a unique variant of Schwann cell tumours having plexiform pattern. Literature revealed only one case of plexiform schwannoma of the jaw bones, i.e. involving the mandible.

CASE REPORT

In this report, we present the first documented case of intraosseous plexiform schwannoma of the maxilla, an extremely rare benign neurogenic tumour treated surgically.

DISCUSSION

Schwannoma is a benign neoplasm originating from the neural sheath of peripheral soft tissues, but to occur within the jaw bones is exceptional. Plexiform schwannoma is a rare variant of Schwann cell tumour having plexiform pattern of intraneural growth with multinodularity. Plexiform schwannoma is a benign neoplasm with no malignant potential, but recurrences are evident if excised incompletely. Plexiform schwannoma has similar clinical and histopathological features as that of plexiform neurofibroma which has high malignant potential; hence, it is imperative to correctly diagnose and differentiate this lesion as treatment modality of these two lesions differs.

Intraoral schwannoma--a report of two cases

Schwannomas, also known as neurilemmomas, are uncommon neoplasms, derived from schwann cells. These neoplasms, although rare, should be considered in the differential diagnosis of slow growing tumour masses of the oral cavity. The growth of these tumours sometimes causes displacement and compression of the nerve of origin, giving rise to clinical signs and symptoms. It can develop at any age and there is no sex predilection. Intraorally, the tongue is the most common site followed by the palate, floor of the mouth, buccal mucosa, lips and jaws. Surgical excision is the treatment of choice for schwannomas, with few reports of recurrence or malignant transformation. In this paper, the authors report two cases of patients with intraoral schwannoma, where the preoperative clinical diagnosis was inconclusive and final diagnosis was established based on radiographic and histopathological examination.

Giant plexiform schwannoma of the tongue

We present the case of a 38-year-old woman that presented with a very slowly enlarging mass of the tongue. MRI revealed a large mass originating in the tongue base and extending to the supraglottic space. Biopsy of this tumor confirmed the diagnosis of schwannoma. An endaural approach allowed complete resection of the tumor. Definitive histopathological examination showed a plexiform schwannoma. Schwannoma or neurilemoma represents a benign tumor potentially affecting any nerve. The head and neck region is a relatively common location for schwannomas, but tongue schwannomas are considered to be rare and pose the problem of both clinical and histological differential diagnosis of tongue masses.

Solitary myxoid neurofibroma of the soft palate

The neurofibroma is a benign tumor of neural origin, not frequently located in the oral cavity, and, especially, extremely rare in the soft palate. When it occurs solitarily, it is a spontaneous tumor without any internal manifestations. We report a case of an isolated neurofibroma of the soft palate not associated with von Recklinghausen disease.

Schwannoma presenting in the soft palate of a nine-year-old boy

Swellings and tumours within the oral cavity are a common finding, however, benign intra-oral schwannoma or neurolemma is relatively uncommon, especially in younger patients. Involvement of the palate is a rare presentation although there have been a few reported cases relating to the lingual and other tissues. This paper reviews intra-oral schwannomas and presents a case of such a tumour of the soft palate in a paediatric patient and discusses the presenting features, differential diagnoses, along with the management of the condition.

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.

Solitary neurofibroma of the gingiva with prominent differentiation of Meissner bodies: a case report

Background

Oral neurofibromas are peripheral nerve sheath tumors, similar to schwannomas. Histological variations in oral neurofibromas are relatively uncommon.

Case presentation

Here, we present a case of unique variation in the observed characteristics of a neurofibroma, with no relation to neurofibromatosis type-1 or von Recklinghausen disease of the skin. The neurofibroma was observed in the right mandibular gingiva of a 32-year-old Japanese woman. Histologically, it differed from conventional neurofibromas in that the tumor was composed of a mixture of fine fibrillary collagen in sheets and/or cords of neoplastic Schwann cells containing numerous clusters of Meissner bodies. Histologically, these bodies were in contact with neoplastic Schwann cells. The Meissner bodies were immunopositive for S-100 protein, neuron-specific enolase, and vimentin, but were negative for calretinin. CD34-positive spindle cells were observed around the Meissner bodies. No recurrence or signs of other tumors have been observed in the patient for 5 years after tumor resection.

Conclusion

To the best of our knowledge, no formal descriptions of sporadic, solitary neurofibromas containing numerous Meissner bodies occurring in the oral cavity are available in literature. We believe that an uncommon proliferation of Meissner bodies, as seen in the present case, may result from aberrant differentiation of neoplastic Schwann cells.

Palisaded encapsulated ("solitary circumscribed") neuroma of the oral cavity: a review of 55 cases

We describe the clinicopathologic characteristics of 55 oral palisaded encapsulated (solitary circumscribed) neuromas (PEN/SCN). Fifty-five cases of PEN/SCN in 54 patients were reviewed. Lesions were categorized according to their histologic pattern, partial or complete encapsulation, presence of Verocay bodies and presence of a parent peripheral nerve. In 13 selected cases immunohistochemical evaluation for neuronal markers (S-100, GFAP, NFP, EMA) was performed. When immunoreaction with EMA was weak, claudin-1 and glut-1 stains were utilized. Thirty-eight patients were men and 16 were women. Mean patient age was 48 years (SD: +/-14). The vast majority involved the masticatory (palate and gingiva) mucosa (76.4%) followed by the labial mucosa, the tongue and buccal mucosa. Recurrence was recorded in only one case. Histologically, 34 lesions had a lobular pattern, 10 were plexiform, 7 fungating and 4 multilobular. Stroma was limited, but focal myxoid changes were seen at the periphery of the lobules. Only one predominantly myxoid lesion was encountered. The number of intralesional axons varied, but the ratio of Schwann cells to axons was generally less than 1:2. Most lesions (89%) were only partially surrounded by perineurium. Tumor cells were S-100 positive and GFAP negative. The parent nerve was identified in 50% of the cases. Overlying epithelium was generally atrophic. Peritumoral connective tissue was generally unremarkable, but chronic inflammation was present in five cases. PEN/SCN is a relatively common peripheral nerve sheath tumor. Generally, its diagnosis is simple. GFAP may be of help to distinguish PEN/SCN from other peripheral nerve sheath tumors (schwannoma, neurofibroma, traumatic neuroma) in cases where histomorphologic features may be confusing. Finally, pathologists should be aware of the occurrence of plexiform and multilobular PEN/SCN variants, to avoid misinterpretation as plexiform neurofibroma or schwannoma.

Schwannomas of the head and neck: a case series

Schwannomas are relatively slow growing benign tumors of the nerve sheath with a well developed capsule. They can reach a considerable size. Typically, symptoms of schwannomas are based on the affected nerve. We present four cases of this tumor that occurred in the head and neck. The differential diagnosis of small painless nodules in head and neck must include schwannomas as it is likely that nerve sheath neoplasms are more common than previously reported. However, due to benign nature and low recurrence prognosis is excellent.