|Year : 2020 | Volume
| Issue : 1 | Page : 48-50
Vocal fold schwannoma in a 13-year-old girl
Santosh Kumar Swain1, Smrutipragnya Samal1, Somadatta Das2, Rabindranath Padhy2
1 Department of Otorhinolaryngology, IMS and SUM Hospital, Siksha “O” Anusandhan University, Bhubaneswar, Odisha, India
2 Central Research Laboratory, IMS and SUM Hospital, Siksha “O” Anusandhan University, Bhubaneswar, Odisha, India
|Date of Submission||23-Dec-2019|
|Date of Acceptance||12-Mar-2020|
|Date of Web Publication||23-Jun-2020|
Prof. Santosh Kumar Swain
Department of Otorhinolaryngology, IMS and SUM Hospital,Siksha “O” Anusandhan University, Bhubaneswar, Odisha
Source of Support: None, Conflict of Interest: None
Laryngeal neurogenic tumors are extremely rare clinical entity. It is a benign and slowly growing neoplasm. Schwannoma of the larynx often arises from the aryepiglottic fold and false vocal cord. Schwannoma of the larynx particularly at the true vocal fold is extremely uncommon. Laryngeal schwannoma typically presents with hoarseness of voice and globus sensation. If the tumor is increases to bigger size, it may lead to dyspnea and stridor. It has an excellent prognosis with low potential for malignant transformation. It should be considered as a differential diagnosis of sublingual pathologies such as salivary gland lesions such as vocal fold polyp. Surgical excision of the tumor is the primary treatment of choice in case of lingual schwannoma. The endoscopic transoral route is considered as the most commonly used approach for vocal fold schwannoma. We report a case of vocal fold schwannoma in a 13-year-old girl which was excised endoscopically.
Keywords: Larynx, microlaryngeal surgery, schwannoma, vocal fold
|How to cite this article:|
Swain SK, Samal S, Das S, Padhy R. Vocal fold schwannoma in a 13-year-old girl. J Sci Soc 2020;47:48-50
| Introduction|| |
Schwannoma is a benign neurogenic tumor which arises from Schwann cells of the peripheral nerve sheath. It is slow-growing, solitary, and encapsulated neoplasm. It is a common neoplasm in the head–and-neck area and around 25%–45% of all schwannomas are found in the head–and-neck region. However, its location in the larynx is extremely uncommon. Neurogenic tumors of the larynx are extremely rare and accounts for approximately 0.1% of all the benign neoplasms of the larynx. These neoplasms of the larynx often arise from the cells of the peripheral nerve including Schwann's cells, perineural cells, and fibroblasts. In the larynx, schwannomas are usually arises in the false vocal folds and aryepiglottic folds. Schwannoma in the true vocal folds is extremely rare and only very few cases documented in the medical literature. These neoplasms of the larynx often arise from the internal branch of the superior laryngeal nerve. Schwannomas are found in the all age group and occur predominantly in female. It can arise from any peripheral, cranial (except olfactory and optic), or autonomic nerves which contain Schwann cells, the cells which form the myelin sheath over the nerve fibers. This tumor may occur alone or associated with genetically inherited disease: neurofibromatosis type 1(NF1) or type 2 (NF2) and schwannomatosis. NF2 gene acts as a tumor suppressor and regulates Schwann cells. Here, we present a case of a vocal fold schwannoma in a pediatric patient.
| Case Report|| |
A 13-year-old girl presented with a progressive dysphonia for 6 months. She had no symptoms of dysphagia. There was no evidence of associated systemic symptoms. She was not exposed to any passive or active smoking and alcohol consumption. Laryngeal endoscopic picture showed a polypoidal mass in the right vocal fold [Figure 1]. Both vocal folds were mobile and no significant airway obstruction was found. The mass was within the laryngeal framework without any cartilage destruction. She was planned for microlaryngeal surgery and biopsy for thinking of vocal fold polyp. Suspension microlaryngoscopy and biopsy were performed under general anesthesia. The polypoidal mass was completely excised by using cold steel instrument. The histopathological examination confirmed the vocal fold schwannoma. Histopathological examination of this tumor showed a circumscribed well-defined lesion covered by a thin lining mucosa. The tumor consists of alternate hypocellular and hypercellular areas made up of spindle-shaped Schwann cells. The hypercellular (Antoni A) areas showed cellular interlacing eosinophilic areas characteristic of Verocay bodies [Figure 2]. The hypocellular areas (Antoni B) showed myxoid change. Immunochemistry of this tumor showed strong S100 positivity in the spindle tumor cells [Figure 3]. Cytokeratin and smooth muscle actin (SMA) were negative in these neoplastic cells. Ki67 staining revealed a low proliferative index. Hence, it was diagnosed with a benign schwannoma arising from the sublingual surface of the tongue. Three weeks postoperatively, the patient reported that her voice had progressively improved. Follow-up flexible fiberoptic laryngoscopy showed the right vocal fold was healing well without any edema or scarring. At 3-month follow-up, fiberoptic laryngoscopic examination revealed normal vocal fold and the patient's voice had improved markedly without any evidence of recurrence.
|Figure 1: Laryngoscopic picture detects a large mass in the right true vocal fold|
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|Figure 2: Schwannoma of the tongue showing spindle cells arranged in a palisading pattern and forming Verocay bodies (Antoni- A area). (H and E stain, ×100)|
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|Figure 3: Schwannoma at the tongue showing strong S-100 reactivity (×200)|
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| Discussion|| |
Schwannomas are an uncommon benign tumor which originates from any peripheral, cranial, or autonomic nerves which contain Schwann cells. These tumors are extremely rare in the oral cavity. These tumors include schwannoma (neurilemmoma or neurinomas), neurofibromas, and traumatic neuroma. Majority of the head-and-neck schwannomas present as slowly enlarging, solitary, nontender, and encapsulated mass. Schwannomas are benign and encapsulated tumor which arises from the spinal roots, cervical nerves, sympathetic nerves, vagus, peroneal, and ulnar nerves. The first neurogenic neoplasm in the larynx was documented by Verocay in 1908. Since then, there are reports accounting for <0.1% of all being neoplasms of the larynx. The common sites for the origin of schwannoma at the larynx are aryepiglottic folds followed by arytenoids, ventricular folds, and vocal folds. The chance of malignant transformation is extremely rare. Patients of laryngeal schwannoma often present symptoms of sore throat, odynophagia, dysphagia, dyspnea, stridor, dysphonia, hoarseness of voice, and foreign body sensation in the throat. In this case, the tumor is seen in the right vocal fold and patients present with hoarseness of voice.
The investigations include the endoscopic examination of the larynx, imaging, histopathological examination, and immunohistochemistry. The endoscopic examination of the larynx includes fiberoptic laryngoscopy and stroboscopy. Endoscopic examinations confirm the site and size of the tumor in the larynx. The imaging-like computed tomography (CT) scan is helpful for the differential diagnosis between schwannoma of the larynx, chondroma, laryngeal cyst, adenoma, and internal laryngoceles. A well-delineated hypodense submucosal mass with slight heterogeneous enhancement without any cartilage erosion is the characteristic of laryngeal schwannoma in the CT scan. Magnetic resonance imaging (MRI) is helpful and superior to delineate soft tissue. In MRI, schwannoma looks strongly enhancing mass with low signal intensity on T1 weighted and high signal intensity on T2-weighted images. CT and MRI are helpful in defining the extent and the nature of the lesion. The lesion typically sharply demarcated as a round or oval and isointense mass with heterogeneous enhancement. Calcifications of the mass reflect degenerative changes in the tumor. Radiologically, schwannoma and neurofibromas cannot be differentiated due to similar findings. In this case, the vocal fold mass confuses with polyp so radiological test like CT or MRI was not done. The differential diagnoses of the vocal fold schwannoma include laryngeal cyst and internal laryngoceles. The confirmation of the diagnosis is done by histological examinations with the presence of spindle cells and typical nuclear palisading and Antoni A and or Antoni B areas and/or Antoni B areas with positive immunohistochemistry for s-100 protein where specific schwannoma cells. The histopathological diagnosis of the schwannoma with the presence of an alternate pattern of Antoni A and B areas, nuclear palisading, Verocay bodies, and whirling of cells is often unequivocal. Histologically, tumors mimicking neurilemmomas are meningioma, leiomyoma/leiomyosarcoma, palisaded fibroblastoma, and pleomorphic hyalinizing angiectatic tumor of the soft tissue. Schwannomas are strongly immunoreactivity for S-100 protein, which is the clue for a diagnosis. Histopathology and immunohistochemistry are useful for the confirmation of the diagnosis.
Surgical excision is the mainstay of treatment for vocal fold schwannoma. A complete excision of the tumor is the treatment of choice. Wide excision of this tumor is required to prevent a recurrence. There will be a rapid growth of this lesion following inadequate excision of this tumor. There are several surgical approaches as per the size of the size and site of the tumor and definitely surgeon's preference. There should be optimum care given for avoiding the mucosal injury. If the tumor is large enough and compromising the glottic airway requires tracheostomy for securing the airway. The surgical approaches depend on the site and size of the schwannoma. Smaller tumors can be removed endoscopically with or without the help of laser. Larger tumors often require external approach such as lateral pharyngotomy, lateral thyrotomy, or laryngofissure approach. Wide excision of the tumor is required to prevent a recurrence. Small laryngeal schwannoma requires endoscopic CO2 laser treatment for a successful outcome with little or no morbidity. Open techniques are useful in the case of large tumors and the techniques are lateral pharyngotomy, lateral thyrotomy, and laryngofissure. In our case, the transoral endoscopic complete excision of the tumor was done with excellent hemostasis and maximum mucosal preservation.
| Conclusion|| |
Despite the rarity of the schwannoma in the vocal fold, this neurogenic neoplasm of the larynx should be recognized. Although there are several imaging options are available, the exact diagnosis of the schwannoma is done by the histopathological examination. Complete excision of the tumor from the vocal fold is the treatment of choice. Malignant transformation of this tumor is extremely rare. Recurrence following surgical treatment is highly uncommon.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
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Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3]