Atypical presentation of sinonasal cellular schwannoma: a nonsolitary mass with osseous, orbital, and intracranial invasion

Rare Schwannomas of Head and Neck and Review of Literature

Benign schwannoma is a slow growing encapsulated tumor arising from the sheath of Schwann, The majority had extra-cranial localization. We report in this review three cases of a rare extra cranial localization of benign schwannoma in the trachea, frontal sinus and intraparotid facial nerve. The first case diagnosed in a 10-years-old boy, presented with a painless, slow growing mass evolving for three years in the left parotidic region, total conservative parotidectomy was done. The second case concerned a 38-years-old, was admitted to the emergency department with acute inspiratory dyspnea, endoscopic exploration revealed a polylobed tracheal tumor, complete tumor excision was done endoscopically. The third case was about a 33 years old patient, presented a gradually enlarging frontal swelling associated with headache and left nasal obstruction, the endoscopic examination revealed a gray pinkish, smooth and firm soft tissue mass occupying the entire left nasal cavity, CT scan and MRI were requested to assess the characteristics and extent of the tumor, The surgical intervention combined two approaches: trans facial through a mid-frontal incision, and endonasal one. Histopathological examination confirmed the diagnosis of benign schwannoma in all these cases.

Schwannoma of the sinonasal tract: case report with review of the literature

Schwannomas of the sinonasal tract are rare, accounting for <4% of head and neck schwannomas. We report the case of a 61-year-old male who presented with unilateral nasal symptoms. Examination and imaging revealed a unilateral polyp at the level of the middle turbinate, with an initial biopsy suggestive of an inflammatory polyp. Due to the persistence of the patient's symptoms and his polyp despite medical therapy, endoscopic nasal polypectomy was performed. The histology surprisingly showed a schwannoma. No further interventions were carried out, and the patient remains disease-free 6 months postoperatively. A review of the literature comprising 60 cases is included. An optimal clinical approach to the investigation and management of schwannomas of the sinonasal tract is subsequently discussed.

Encapsulated Sinonasal Schwannoma Mimicking an Antrochoanal Polyp

Extracranial schwannomas are uncommon neoplasms of the sinonasal tract arising from peripheral nerve shealth. Mostly acapsulated on histology, but few cases of encapsulated schwannomas have been reported. Its symptoms are nonspecific and initial clinical diagnosis is frequently missed. We report a 13-year-old boy with a huge, encapsulated sinonasal schwannoma initially thought to be an antrochoanal polyp. Computed tomography scan demonstrated a huge irregularly shaped mildly enhancing isodense mass in the right nasal cavity with lateral extension to the ipsilateral maxillary sinus, superior extension into the ethmoids and frontal sinuses and posteriorly into the nasopharynx. The tumour was completely excised via a lateral rhinotomy and patient is still on follow-up.

Atypical presentation of cystic schwannoma of the sphenoid sinus: a nonsolitary mass with osseous, intracranial and cavernous sinus invasion

Although nearly half of all schwannomas involve the head and neck region, nasal and paranasal sinus presentations are quite rarely seen. Cystic schwannoma, characterized by cyst formation lined by S-100 protein positive membrane-like structures is very uncommonly seen in sphenoid sinus with only a single previously reported case. Here we report a young patient of cystic schwannoma of the paranasal sinuses having epicenter in the sphenoid sinus. The tumor had caused extensive erosion of the skull base and paranasal sinuses and extended intracranially that radiologically mimicked as infected mucocele causing loss of vision. This case denotes the aggressive behavior of such uncommon tumors.

A review of nasal, paranasal, and skull base tumors invading the orbit

Tumors that invade the orbit are uncommon. The majority are meningiomas arising from the sphenoid ridge (66%). Others are bone and cartilage tumors arising from the surrounding bones of the orbit, pituitary adenomas, and epithelial tumors arising from the paranasal sinuses and nasal cavity. Meningiomas occur more often in women, whereas epithelial tumors have a predilection for men. Meningiomas and epithelial tumors typically present in the sixth decade of life, whereas bone tumors tend to affect individuals in their third decade of life. Patients often present with a combination of ophthalmological and otorhinolaryngological symptoms, including proptosis, pain, decreased visual acuity, restrictions in motility of the eye, epistaxis, and nasal obstruction. Sarcomas and benign bone and cartilage tumors arise from surrounding structures, whereas carcinomas usually arise from the paranasal sinuses. Surgery is the mainstay of treatment. Depending on the aggressiveness and histology of the tumor, surgery may be combined with radiation and chemotherapy. The prognosis is generally poor, but varies depending on histology and cell origin, size of the tumor, and degree of invasion. Meningiomas and benign bone tumors have the best prognoses. Sinonasal undifferentiated carcinomas, small-cell neuroendocrine carcinomas, osteosarcomas, and rhabdomyosarcomas have poorer prognoses.

Giant Primary Schwannoma of the Left Nasal Cavity and Ethmoid Sinus

A unilateral tumour in the nasal cavity or paranasal sinuses is commonly caused by polyps, cysts, and mucoceles, as well as invasive tumours such as papillomas and squamous cell carcinomas. Schwannomas, in contrast, are rare lesions in this area (Minhas et al., 2013). We present a case of a 52-year-old female who presented with a 4-year progressive history of mucous hypersecretion, nasal obstruction, pain, and fullness. Imaging of the paranasal sinuses showed complete opacification of the entire left nasal cavity and sinuses by a tumour causing subsequent obstruction of the frontal and maxillary sinuses. The tumour was completely excised endoscopically. Histopathology was consistent with that of a schwannoma.