Primary nasal meningioma-a case report

Extracranial meningiomas may be subdivided into primary (PEM) and secondary types based on absence or presence of intracranial attachments respectively. Primary sinonasal tract meningiomas are rare with unknown etiopathology and non-specific clinical presentation. Of these PEMs, only 11.5% are in the nasal cavity and nasal septum. To our knowledge less than 50 cases of PEM of nasal cavity have been reported in the literature. We report a case of a 22 years old male who presented with epistaxis and increasing nasal stuffiness for the last one year. ABSTRACT


INTRODUCTION
Meningioma is a common tumor accounting for 15% of all intracranial tumors. 1  Extracranial meningiomas (EM) are rare comprising less than 2% of all meningiomas and sites such as spine, nasal septum, neck, chest, shoulder, peritoneum have been reported.1,2  Extracranial meningiomas may be subdivided into primary (PEM) and secondary types based on absence or presence of intracranial attachments respectively.Of these PEMs, only 11.5% are in the nasal cavity and nasal septum.To our knowledge less than 50 cases of PEM of nasal cavity have been reported in the literature. 2

CASE REPORT
A 22 years old male presented in the emergency with continuous nasal bleeding from left nostril for 10 hours.He Ghosh A 1 , Ghartimagar G 1 , Thapa S 1 ,Shrestha MK 2 , Talwar OP  meningothelial meningioma was given.Repeat CT scan did not show any intracranial involvement and confirmed the primary nature of the tumor.On postoperative follow up of 3 years, patient is doing well.

DISCUSSION
The origin of primary extracranial meningiomas is unclear.
Several theories suggest that these lesions arise from arachnoid cells in nerve sheaths, ectopic arachnoid cells entrapped extra-cranially during neural tube closure and pleuripotent mesenchymal cells. 3,4In one series, mean age for nasal meningiomas was 28 with 40% being below 20 yrs of age. 4 Among PEMs, females are more affected in petrous and sinonasal meningiomas, males are affected more in cutaneous meningiomas while for other sites there is no gender predilection.Our case, however, was a 22 year male with sinonasal meningioma.Clinically most patients present with non-specific symptoms including nasal stuffiness, episodes of epistaxis, hydrorrhea, hyposmia and headache. 3,4Under nasal endoscopy, usually it presents as pink to grey well circumscribed lobulated mass which may or may not bleed.On radiology, calcification and local invasion may mimic malignant tumor. 5stological diagnosis may be difficult to establish because of their uncommon ectopic site and non specific clinicradiological appearance. 1 The microscopic features are characteristic in meningothelial type but may be less typical in other histological forms. 1,2Histological differentials include carcinoma, melanoma, olfactory neuroblastoma and ossifying fibroma. 6Our case showed classical meningothelial pattern with presence of intranuclear inclusions and psammoma bodies and absence of mitosis, anaplasia and necrosis.Positivity to vimentin, EMA, S-100, keratin may be helpful in difficult cases. 7O classifies meningioma into 3 categories viz., grade I (>80%) as benign meningioma, grade II (5-15%) as atypical meningioma with frequent mitosis and grade III (1-2%) as anaplastic type. 8Four major histological varieties include meningothelial, fibroblastic, transitional and angioblastic.The most common form is meningothelial meningioma as in our case.
Whenever surgery is possible, complete resection is the treatment of choice and if surgery is not possible, adjuvant radiotherapy is necessary to stabilize the lesion. 1 Recurrence rate after surgery varies as widely as 7 to 84% in different   series. 3In our case, the patient is from nearby area and is on regular follow up.The slides with initial diagnosis of oxyphilic adenoma at the age of 12 years were reviewed which showed similar morphological picture.So the current presentation may be considered as recurrence.However intracranial extension was not found which is a good prognostic factor for the patient.

CONCLUSION
Primary sinonasal tract meningiomas are rare with unknown etiopathology and non specific clinical presentation.
Confirmation of the diagnosis rests on histological examination.The prognosis is excellent after complete surgical removal without adjuvant therapy.Regular follow up is mandatory to rule out recurrence.

Figure 1 :
Figure 1: Plain non-contrast CT. (A) Coronal reformatted images and (B) Axial image, soft tissue window showing left soft tissue density in the nasal cavity inseparable from inferior turbinate and extending to middle ethmoidal air cells.Left maxillary sinus shows fluid level.