An Exceptional Case of Intraparotid Plexiform Neurofibroma Originating from Autonomic Fibers of the Auriculotemporal Nerve

Intraparotid plexiform neurofibroma: A rare diagnostic challenge

Isolated intraparotid neurofibromas are exceptionally rare and often associated with neurofibromatosis type 1 (NF1). Diagnosing these tumors proves challenging because of the clinical resemblance to primary salivary gland masses. This case report details an 18-year-old with a painful, enlarging parotid mass, diagnosed through fine needle aspiration biopsy (FNAB) revealing myxoid stroma and spindle cells. Magnetic resonance imaging confirmed a plexiform neurofibroma involving the parotid gland and facial nerve. Histopathology validated the diagnosis, emphasizing the importance of cytological and radiological correlation. Notably, the absent NF1 association makes this case unique. Surgical excision with facial nerve reconstruction was performed, highlighting the complexity of managing such rare intraparotid neurofibromas. Awareness of this entity is crucial for accurate diagnosis and appropriate management.

Intraparotid Ganglioneuroma: A rare case report

Introduction: Ganglioneuromas (GNs) are slow-growing, benign tumors arising from Schwann cells, gangliocytes, and neuronal tissues. Case Presentation: We report a rare intraparotid ganglioneuroma in a 42-year-old female presented with a parotid mass. The onset of the lesion dated back to 2021, but the growth was remarkable only in November 2022. The FNA suggested a plexiform neurofibroma. The post-surgical microscopic examination of the excised lesion revealed neoplastic large, rounded cells with abundant, finely granular eosinophilic cytoplasm and a large, eccentric nucleus with a prominent nucleolus as well as fasciculated, with an elongated cytoplasm with fine fibrillar extensions. No mitosis or tumor necrosis was observed. The periphery of the tumor showed perineural entrapment. The immunohistochemical staining for S100 protein, synaptophysin, and chromogranin A were positive. However, the neoplastic cells showed no immunoreactivity for cytokeratin (CK5/6, CK7, AE1/AE3), epithelial membrane antigen, HMB45, Melan A, CD30, CD117 and p40. The case was signed out as mature intraparotid ganglioneuroma. Conclusion: The treatment of choice was surgical resection without adjuvant radiotherapy. No recurrence or post-surgical complications were hitherto reported. To the best of our knowledge, this is the first reported case of intraparotid ganglioneuroma. Caution should be taken not to diagnose this benign neoplasm as a metastasis (e.g. metastatic neuroblastoma) or to request unnecessary overtreatment (e.g., postoperative chemotherapy and radiotherapy).

Intranodal Neurofibroma: A Case Report and Literature Review

PURPOSE

To report a case of neurofibroma involving the lymph nodes and to perform a literature review on this topic.

OBSERVATIONS

A 72-year-old woman with a history of neurofibromatosis and biopsy-proven malignant melanoma of the left forearm underwent wide local excision of the malignant lesion along with sentinel axillary lymph node biopsy. Histological examination of axillary nodes revealed diffuse neurofibromatosis within 2 lymph node capsules. A thorough review of the English literature pertaining to intranodal neurofibroma was performed by querying Google Scholar and PubMed. Only 5 cases of intranodal neurofibroma have been described until now.

CONCLUSIONS AND IMPORTANCE

Neurofibroma involving the lymph nodes is rare and this is the first reported case that is shown to diffusely involve the intracapsular space. Furthermore, intranodal neurofibroma can represent a diagnostic pitfall in the evaluation of sentinel lymph nodes for metastatic melanoma.

Isolated neurofibromas of the great auricular nerve: A rare localization in a pediatric patient with neurofibromatosis type-1

Peripheral nerve sheath tumors encompass a spectrum of well-defined clinicopathologic entities, ranging from benign tumors, such as neurofibromas, to high grade malignant neoplasms termed malignant peripheral nerve sheath tumors. Morphologic variability of these tumors is wide, and they engender some of the most controversial, difficult differential diagnoses. Localized neurofibromas often involve a major nerve and result typically in fusiform expansion of the nerve trunk (intraneural subtype). We report a case of circumscribed solitary neurofibromas in a 14-year-old boy with NF1 who presented to our department with a left neck swelling. The neurofibromas lesion involved the anterior branch of the great auricular nerve. The sensory symptoms initially reported by the patient (paresthesia and hyperesthesia) in the lower preauricular region. Surgical treatment represents the therapeutic method of choice in the approach to neurofibromas, considering functional disorders and possible aesthetic deformities. The case described presented difficulties in surgical excision, based on risk of functional and aesthetic results.

Intraparotid facial nerve plexiform neurofibroma in a child (case report)

Background

Intraparotid facial nerve neurofibromas are benign neoplasms, extremely rare, difficult to diagnose and to manage. Only three pediatric cases have been reported in the literature.

Case presentation

We report the 4th case of a 7-year-old child admitted for a parotid mass without facial palsy, for whom the surgical indication was the increase in volume of this mass, as well as the aesthetical impairment, the surgical exploration found the tumor attached to the lower branch of the division of the facial nerve. The excision of the mass was performed with the sacrifice of the inferior branch of the facial nerve, the trunk and the upper branch of the facial nerve was preserved, the pathological study was in favor of a plexiform neurofibroma.

The patient has presented postoperatively a grade 5 facial palsy in the inferior territory of the facial nerve with a slight recovery 1 year after surgery.

Conclusion

Even though plexiform neurofibromas in the parotid gland are extremely rare, and their diagnosis are not often primary evoked in front of any growing mass of this region, the surgeon must keep in mind the existence of these neoplasms as a differential diagnosis of a parotid tumor.

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Neurofibromas are non-encapsulated tumors that grow inside the nerve that surrounds each nerve fascicle and lengthen them, locally invasive, non-metastatic, highly vascularized, and slow-growing.

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Our patient is the 4th isolated case of intraparotid facial nerve plexiform neurofibroma without neurofibromatosis type 1.

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Preservation of the nerve during surgery is almost impossible and its excision can lead to significant morbidity.

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It is essential that the surgeon keep in mind the existence of these tumors as a differential diagnosis of a parotid tumor.