Clinicopathologic and immunohistochemical features of oral neurofibroma

An Unusual Intraosseous Swelling of the Jaw: Two Rare Case Reports

Neurofibroma is the most common type of peripheral nerve neoplasm arising from a mixture of cell types, including schwann cells and perineurial fibroblasts. We report two unusual cases where patients presented with intraosseous swelling of the jaw. A complete examination followed by Imaging and histopathological examination were advised. Imaging showed ill-defined radiolucency in one case and well defined corticated radiolucency with soap-bubble appearance in the other case. Biopsy with adjuvant immunohistochemistry revealed features suggestive of neurofibroma. Both cases were managed surgically. The second case in the male patient, also showed multiple recurrences and subsequent transformation into atypical neurofibroma. In spite of being a benign tumor, neurofibroma is locally aggressive. Commonly found in soft tissues of the body, neurofibromas are rare in the head and neck region. But the intraosseous location of this tumor in the mandible is an exceptional case.

Intraoral neurofibroma: A case report with emphasis on immunohistochemical markers

ABSTRACT

A neurofibroma is a benign peripheral nerve sheath tumor. They occur in combination with neurofibromatosis or as a solitary mass. Intraoral neurofibromas pose diagnostic difficulties, suggesting the appropriate use of diagnostic markers and clinical knowledge. Here, we report a case of intraoral neurofibroma in a 57-year-old female who reported with the complaint of painless growth in the lower left back tooth region for the past three years. Based on the clinical features, provisional diagnosis of traumatic fibroma was made. However, histopathology proved it to be a benign spindle cell lesion; upon further investigation by immunohistochemistry, it was diagnosed to be a case of neurofibroma.

MRI findings of benign tumors and tumor-like diseases of the tongue with radiologic-pathologic correlation

Benign tumors or tumor-like lesions of the tongue are uncommon lesions that comprise a heterogeneous group of neoplasms. Although there are a variety of benign tumors or tumor-like lesions, the imaging appearance of these diseases is not well defined because of a paucity of scientific literature on this topic. Most benign tongue tumors usually appear as submucosal bulges located in the deep portion of the tongue. Their true features and extent may only be identified on cross-sectional images such as CT and MRI. Thus, CT and MRI play an important role in the diagnosis of these unusual lesions. It is important that radiologists be able to identify the characteristic CT and MR imaging features that can be used to narrow the differential diagnosis with increased diagnostic confidence, suggest specific histologic tumor types. In this pictorial essay, we provide insights into the MRI presentations of benign tongue tumors and tumor-like diseases and their radiologic-pathologic correlation. Benign tumors or tumor-like lesions of the tongue described herein include papilloma, lipoma, hemangioma, venous malformations, schwannoma, neurofibroma, epidermoid cyst, and dermoid cyst.

Type I Neurofibromatosis: Case Report and Review of the Literature Focused on Oral and Cutaneous Lesions

Neurofibromatosis type 1 (NF1) is a common genetic disease whose dermatological lesions are at the forefront of its development. Cutaneous manifestations include café au lait spots, intertriginous freckling, and neurofibromas which appear during childhood and adolescence and are part of the clinical criteria to diagnose NF1. However, it is only recently that oral manifestations have been highlighted in many studies as frequently associated to NF1. This article aims to review oral and cutaneous manifestations related to NF1 and to report a case of a 51-year-old male with skin and oral neurofibromas related to NF1. Our patient presented with lesions on the gingiva, a rare localization that takes a hypertrophic form mimicking other various pathological conditions. Although not frequent, malignant transformation in NF1, especially regarding plexiform neurofibromas, is well established. Patients with NF1 therefore have regular follow-ups based on clinical examination, as sarcomatous transformation brings an extremely poor prognosis, recurrences and distant metastasis being common.

Prevalence of oral neurofibroma in Central Indian population: A retrospective study of 20 years

CONTEXT

Neurofibroma is a benign peripheral nerve sheath tumor. Commonly found in the peripheral soft tissues, it can manifest as a solitary mass or as a component of neurofibromatosis.

AIMS

The purpose of the retrospective cross-sectional study was contributing to the literature by providing data about the prevalence of oral neurofibroma in Central Indian population.

SETTINGS AND DESIGN

Retrospective, cross-sectional study.

SUBJECTS AND METHODS

All histopathologically diagnosed cases of oral neurofibroma were retrieved from the archives of our department and were reviewed. All the cases that met the inclusion criteria were reviewed in terms of the year when the patient reported, patient's age, gender, location of the lesion, i.e., soft tissue or intraosseous, clinical appearance, i.e., growth or swelling, histopathologic diagnosis and immunohistochemistry results if available. The results were aggregated and described qualitatively using Microsoft Excel 2013.

RESULTS

In our retrospective analysis of 20 years (2000-2019), we came across 14 reported cases of oral neurofibroma, in five males and nine females. Two of these cases showed a recurrent nature and one case showed transformation into atypical neurofibroma. Two cases were encountered in the mandible as an intraosseous oral neurofibroma.

CONCLUSIONS

In our study, we found that oral neurofibroma was more common in the third decade with a female predilection. Gingiva was the most common site. Of the 14 cases that were encountered, two cases showed recurrence and one case showed malignant transformation. Hence, in spite of being a benign neoplasm, oral neurofibroma is locally aggressive and should be diagnosed accurately.

Immunoexpression of BDNF, TrkB, and p75NTR receptors in peripheral neural lesions of the head and neck

BACKGROUND

Brain-derived neurotrophic factor (BDNF) and neurotrophin receptors have been recognized as fundamental regulators of normal brain development, homeostasis, and plasticity. They have also been studied in the behavior of central nervous system tumors. Here, we studied the pattern of BDNF, TrkB and p75NTR immunoexpression in peripheral benign and malignant neural lesions in head and neck.

METHODS

This cross-sectional analytical study included 79 cases of head and neck neural lesions. Nineteen cases of traumatic neuromas (TN), 20 cases of granular cell tumors (GCT), 16 cases of neurofibromas (NF), 20 cases of schwannomas (SC), and 4 malignant peripheral nerve sheath tumor (MPNST) were submitted to immunohistochemistry with BDNF, TrkB, and p75NTR antibodies. A semi-quantitative analysis was performed.

RESULTS

The analysis of BDNF demonstrated a high percentage of positive cells in TN, GCT and SC with a decrease in cases of NF and MPNST. TrkB presented a lower significant immunoexpression in GCT in relation to the TN, NF, SC, and MPNST (P < .0001); and TN showed less percentage of positive cell compared to SC (P = .0017). Regarding p75NTR, the percentage of positive cell was significantly reduced in MPNST compared GCT (P = .009), NF (P = .0138) and SC (P = .0069). Also, a decrease in TN compared to GCT (P = .007) was observed.

CONCLUSIONS

Our results showed the immunoreactivity of BDNF, TrkB, and p75NTR in head and neck peripheral neural lesions. Reduction of BDNF and p75NTR in MPNST might suggest down-regulation during the acquisition of malignant phenotype.

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.

Solitary neurofibroma of the floor of the mouth: rare localization at lingual nerve with intraoral excision

Background

Neurofibromas (NF) are benign tumors of the peripheral nerves that are composed of Schwann cells, perineural-like cells and fibroblasts. The differential diagnosis for a solitary intraneural variant of neurofibroma arising in the floor of the mouth is broad and includes a submandibular gland neoplasm and adenopathy, among others. The intraoral approach is the best choice for a medium-sized lesion.

Case presentation

We report a rare case of a solitary neurofibroma of the floor of the mouth in a 31-year-old male. The patient consulted the dental emergency department for acute pain of the left mandible. Systematic clinical examination revealed the presence of a mass in the left mouth floor. The panoramic x-ray was not conclusive and the magnetic resonance imaging (MRI) revealed a well-defined soft tissue lesion with homogenous isosignal intensity on the T1-weighted image, high intensity signal on the T2-weighted image and heterogeneous enhancement following contrast-enhancement on the T1-weighted Fast Sat image. The surgical excision of the soft-tissue neoplasm was accomplished by an intraoral approach. The specimen was sent for histopathologic analysis and Immunohistochemical studies which confirmed the diagnosis of a myxoid predominant intraneural solitary neurofibroma.

Conclusion

The diagnosis of neurofibroma was confirmed by histopathological evaluation and immunohistochemical studies which also excluded other entities in the histopathologic differential diagnosis including schwannoma and a malignant peripheral nerve sheath tumor among other. Localized (solitary) neurofibromas most often occur as sporadic lesions, however; diagnosis of a solitary neurofibroma prompts clinical evaluation to exclude the remote possibility of neurofibromatosis. The purpose of this case report is to raise awareness of the uncommon presentation of neurofibroma and to document the successful management of such a lesion using an intraoral approach.

Common conditions associated with mandibular canal widening: A literature review

Purpose

The aim of this study was to review the common conditions associated with mandibular canal widening.

Materials and Methods

General search engines and specialized databases including Google Scholar, PubMed, PubMed Central, Science Direct, and Scopus were used to find relevant studies by using the following keywords: “mandibular canal,” “alveolar canal,” “inferior alveolar nerve canal,” “inferior dental canal,” “inferior mandibular canal,” “widening,” “enlargement,” “distension,” “expansion,” and “dilation.”

Results

In total, 130 articles were found, of which 80 were broadly relevant to the topic. We ultimately included 38 articles that were closely related to the topic of interest. When the data were compiled, the following 7 lesions were found to have a relationship with mandibular canal widening: non-Hodgkin lymphoma, osteosarcoma, schwannoma, neurofibroma, vascular malformation/hemangioma, multiple endocrine neoplasia syndromes, and perineural spreading or invasion.

Conclusion

When clinicians encounter a lesion associated with mandibular canal widening, they should immediately consider these entities in the differential diagnosis. Doing so will help dentists make more accurate diagnoses and develop better treatment plans based on patients' radiographs.

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.

Adult hippocampal ganglioneuroblastoma: Case report and literature review

RATIONALE

Intracranial ganglioneuroblastoma represents a rare subtype of primitive neuroectodermal tumor. Here, we report a hippocampal ganglioneuroblastoma and a literature review of cerebral anglioneuroblastoma is carried out.

PATIENT CONCERNS

We report a 16-year-old male patient presenting with absence seizure and high-infiltration hippocampal ganglioneuroblastoma.

INTERVENTIONS

Magnetic resonance imaging (MRI) indicates a space-occupying lesion with a well-defined margin in the right temporal lobe and hippocampus. However, hyper-signal on flair and diffusion-weighted imaging (DWI) with a low apparent diffusion coefficient (ADC) value is detected, which prompts high tumoral invasiveness.

INTERVENTIONS

A total resection of tumor and subsequent chemotherapy combing with radiotherapy is performed.

OUTCOMES

For a follow-up period of 60 months, no evidence of recurrence and further seizures are detected.

LESSONS

High-infiltration hippocampal ganglioneuroblastoma is a rare event. MRI examination often showed features of low-grade gliomas, while hyper-signal lesion on DWI with a low ADC value can be detected. Complete resection combined with fractionated radiotherapy and chemotherapy was the optimal treatment for cerebral ganglioneuroblastoma.

Lingual neurofibroma causing dysaesthesia of the tongue

Neurofibroma is a benign tumour derived from the neural sheaths of peripheral nerves and composed of Schwann cells, fibroblast-like cells and intermediate cells. The usual clinical presentation of an oral neurofibroma is swelling. A 62-year-old woman was referred to our department of otorhinolaryngology with irritation and dysaesthesia of the lateral aspect of the tongue. The only finding was a slightly red area from which a biopsy was taken. The macroscopic findings observed by the surgeon were consistent with normal tongue tissue. The histopathological examination showed a small, rounded tumour closely approximated to an invagination of the surface epithelium and with a small lymphatic infiltrate. The tumour was a neurofibroma. A Schwannoma type B was considered but the presence of small nerves and positive neurofilament reaction favoured a neurofibroma. The patient had no other neurofibromas or skin lesions. At a 3-week follow-up visit all symptoms had resolved.

Solitary plexiform neurofibroma of the gingiva: unique presentation in the oral cavity

Neurofibromas are benign tumours originating from the nerve sheath. Amongst the histological variants, plexiform types are considered exclusive. These are poorly circumscribed, locally invasive and may exhibit sarcomatous potential. Plexiform neurofibromas are key features of Neurofibromatosis - 1 and their solitary intra-oral presentation is uncommon. The following case report describes a unique case of an isolated solitary plexiform neurofibroma of the maxillary anterior gingival region in a middle aged female patient.