A Rare Case Report of Nasal Schwannoma

Abstract

Schwannoma is a rare mass that is benign. It develops from the Schwann cells found in the peripheral nerves. Schwannomas consists of spindle cells exhibiting two unique histological patterns, which may be combined: Antoni type A and type B. When evaluating individuals who have a polyp-like growth in their nose and complain of one-sided nasal blockage, it is crucial to take into account the possibility of a schwannoma as part of the potential diagnoses. A 70-year-old female patient arrived with a gradual and persistent obstruction of the nasal passages over a period of six months. A polypoidal reddish mass was observed in the middle meatus during nasal endoscopy. Endoscopic transnasal excision was carried out. Additionally, a middle meatal antrostomy was done. The potential differential diagnoses encompass carcinoma, inverted papilloma, sarcoma, lymphoma, and neurofibroma. The most recommended method for treating nasal schwannoma is transnasal endoscopic surgery.

Introduction

Schwannoma originates from the Schwann cells found in the peripheral nerves. The tumor is neurogenic in nature and is benign [1, 2]. Additionally, it has a modest growth rate. The tumor exhibits a strong tendency to occur in the head and neck area, with reported occurrence rates ranging from 25 to 45%. Nevertheless, a mere 4% of the instances are reported in the sinonasal tract [3].

The majority of schwannoma instances exhibit no symptoms. If there is pain or neurologic symptoms, they are typically linked to a pressure effect [4]. Small masses are monitored for several years until the patient experiences pain and sensory abnormalities. Once it becomes a cause for concern, it is imperative that it is surgically extracted.

It is usually smooth and nodular, facilitating the normally effective excision of the mass. Occasionally, the nerve of origin can be observed [5].Immunohistochemistry testing is a useful and recommended method in the process of differentiation [6].

Schwannomas exhibit various histopathological variants: (1) Ordinary, (2) Relating to cells, (3) Arranged in a network, (4) Containing melanin, (5) Resembling epithelial cells, (6) Very old. These tumors primarily occur in the peripheral nervous system of the limbs and the head and neck region. Neurilemmomas in the head and neck region account for around 25–40% of all cases [7].

Case Presentation

A 70 year old female presented to the otorhinolaryngology department at tertiary care center with complaints of gradual and persistent obstruction of the nasal passages over a period of six months. No other specific history was noted. Patient is a known case of systemic hypertension, CAD and Dyslipidemia.

Local Examination of Nasal Cavity

On examination of nasal cavity, External frame work appears normal. Right side nasal cavity was free. On the left side, Proliferative Mass, not able to probe laterally, does not bleed on touch noted. Cotton wool test showed decreased vibration on the left side. Cold spatula test performed and resulted in decreased fogging on the left side. Cottle’s test negative. PNS tenderness was elicited and absent.

Management

Routine investigations were done and elevated sugar levels were optimized. Nasal endoscopy was done, and A polypoidal reddish mass was observed in the middle meatus. CT PNS done and reported as Total soft tissue opacification of left ethmoidal sinus with extension of soft tissue compound into left nasal cavity, widening of left nasal cavity with thickening and remodeling of bones (nasal septum, medial wall of left maxillary sinus), Soft tissue opacification of left maxillary, bilateral sphenoid and frontal sinus associated with occlusion of left Osteomeatal complex, left frontoethmoid and sphenoethmoid sinus, suggestive of ethmoidal polyposis (Fig. 1).

Fig. 1.

Axial cuts of CT PNS showing mass (green arrow) in the left maxillary, ethmoid, sphenoid and frontal sinuses

The patient was scheduled for endoscopic excision of the mass. Under strict sterile conditions and under GA, Orotracheal intubation was done. 4% xylocaine with adrenaline nasal packing done. Preliminary DNE done which showed mass arising from the left middle turbinate pushing the septum and multiple blood vessels were noted over the surface of the mass and the same cauterized (Fig. 2). A wide bore needle is inserted into the mass and aspirated. No fluid was aspirated from the mass. Using a microdebrider and blakesley forceps the soft tissue inside the encapsulated mass is debulked and dissected in pieces (Fig. 3). The capsule from the mass is dissected in toto and removed from the nasal cavity (Fig. 4). Anterior and posterior ethmoidectomy done. Frontal recess opened and ostium widened. Mucopurulent discharge drained from the frontal sinus, sphenoidotomy done. Left middle meatal antrostomy was done, hemostasis was achieved throughout the procedure. The patient was extubated and shifted to the post-operative care unit in stable condition.

Fig. 2.

Mass seen arising from middle meatus of left nasal cavity

Fig. 3.

Excision of the mass being done trans nasal endoscopically

Fig. 4.

Left nasal cavity after excision of the mass

Results

Biopsy results showed a tumor with hypocellular areas with focal myxoid change and verocay bodies. The cells are spindled with wavy nucleus and ill-defined cytoplasm. Few areas show many round to oval epithelioid cells having large vesicular nuclei, bizarre forms, and occasional nuclear grooves. Areas of cystic degeneration and hyalinization were noted. No atypical mitosis/ necrosis was seen. The report was thus consistent with Ancient Schwannoma. The patient was then discharged and reviewed on a regular basis. There is no evidence of recurrence of the lesion till date.

Discussion

A schwannoma is a noncancerous mass that originates from the Schwann cells found in the peripheral nervous system. There is no gender related predominance for the disease [8].The possible diagnoses to consider are carcinoma, inverted papilloma, sarcoma, lymphoma, and neurofibroma [9].Determining the origin of nasal schwannomas is challenging due to the thin nerve innervation in the nose. The identification of its nerve connection poses challenges during surgical procedures. The likely origin of these nerves is believed to be either sympathetic, parasympathetic, or sensory [10]. In our case, there was one sided nasal obstruction. Obstruction of the nasal cavity is the most prevalent feature, followed by rhinorrhea and epistaxis. Other features includes decrease or absence of smell, headache or even swelling of the face.

There was a polypoidal tumor in the middle meatus of the left nasal cavity in this patient. Nasal schwannoma typically presents as a polypoidal mass without any unique characteristics [11].

Imaging investigations are necessary to accurately estimate the extensiveness of the lesion and for pre-operative planning, although it may not be useful for its confirmation. There can be erosion of the surrounding bone without complete destruction identifiable on CT.

The presence of schwannoma is verified through histological examination. Schwannomas consist of spindle cells exhibiting two histologically different types: hypercellular area with nuclear palisades, and areas with lower cellularity. The former is known as Antoni Type A and the latter is called Antoni type B (Fig. 5) [12].

Fig. 5.

Histological slide showing Hypercellular (Antoni Type (A) and hypocellular (Antoni Type (B) areas with areas of cystic degeneration and hyalinization

These hypocellular alterations is typically due to the degradation of the mass due to aging. The word “ancient” is used to describe a schwannoma with a lesser number of cells in the connective tissues. Nevertheless, it exhibits comparable characteristics to other forms of schwannoma in regard to its rate of growth and potential for becoming malignant [13].

Surgery is the primary treatment modality for this condition. The methods employed may differ depending on its dimensions and extent. Initially an external approach was used for such cases. But with increasing advancements of endoscopy, it has become the principal surgical method of choice and thus the transnasal endoscopic approach should be considered the most favorable method of operative approach. It is advisable to keep the patient on periodic follow-up even though the rate of recurrence is very low.

Conclusion

It is imperative to extensively evaluate a case of proliferative nasal mass as there is a chance of nasal schwannoma which are rare but benign lesions. Nasal block which is unilateral in nature, is the usual mode of presentation. Transnasal approach can be done for such tumors. Histopathological examination of the removed specimen clinches the diagnosis. Routine follow-up can be advised to watch for recurrence.

Declarations

Ethical Approval

As per university standards written ethical approval has been collected and preserved by the author(s).

Consent to Participate

As per university standards, Participants’ written consent has been collected and preserved by the author(s).

Competing Interests

The authors have declared that no competing interests exist.