|LETTER TO EDITOR
|Year : 2019 | Volume
| Issue : 1 | Page : 221-222
Ancient schwannoma of the parotid gland: A note on surgical management
Joyce P Sequeira, Jagadishchandra, MS Mithun, Sujesh Viswanathan
Department of Oral and Maxillofacial Surgery, Yenepoya Dental College, Mangalore, Karnataka, India
|Date of Web Publication||13-Jun-2019|
Dr. M S Mithun
Sabarigiri, Cherumoodu, Vellimon P.O, Kollam - 691 511, Kerala
|How to cite this article:|
Sequeira JP, Jagadishchandra, Mithun M S, Viswanathan S. Ancient schwannoma of the parotid gland: A note on surgical management. Ann Maxillofac Surg 2019;9:221-2
|How to cite this URL:|
Sequeira JP, Jagadishchandra, Mithun M S, Viswanathan S. Ancient schwannoma of the parotid gland: A note on surgical management. Ann Maxillofac Surg [serial online] 2019 [cited 2020 Jan 20];9:221-2. Available from: http://www.amsjournal.com/text.asp?2019/9/1/221/260336
Schwannoma (neurilemmoma) is a benign tumor of the nerve sheath origin which can arise from any nerve covered with a Schwann cell sheath, which includes the cranial (except for optic, olfactory), spinal, and autonomic nervous system. Differential diagnoses for such tumors are often a dilemma for a clinician as these show almost similar clinical pictures with various other conditions such as schwannoma, lipoma, benign salivary gland tumors, and lymphoma. We report a case of schwannoma of the parotid gland, its diagnosis, and surgical management.
A 65-year-old patient reported to our outpatient department, with a chief complaint of swelling and dull-aching pain over the right preauricular region for 3 years. The patient gave a history of visiting a local clinic for the same, where primary care with antibiotic and nonsteroidal anti-inflammatory drugs was prescribed, and there was no relief in symptoms. On examination, swelling appeared single, firm, nonfluctuant, noncompressible, and nonpulsatile which was tender on palpation measuring 4 cm × 5 cm was present on the right preauricular region; 2 cm anterior from the tragus of the ear to the malar prominence and superoinferiorly from the tragus to the point 3 cm above the angle of the mandible covered by normal skin [Figure 1]. The facial nerve functions were normal. The patient denied otalgia, fever, weight loss, or night sweats. The remainder of the physical examination, including head and neck, was normal. On intraoral examination, no relevant finding was noticed. The corresponding buccal mucosa to the extraoral swelling appeared normal. On milking of Stenson's duct, the salivary flow and consistency were normal with and without stimulation.
Ultrasonography and fine-needle aspiration biopsy were nonconclusive suggesting benign cystic contents. Contrast-enhanced magnetic resonance imaging (MRI) revealed a well-defined area of altered signal intensity showing mixed in T1 and T2 with node enhancement within the right masseter muscle [Figure 2].
The patient underwent surgical removal of the mass by reflecting superficial lobe of parotid giving preauricular incision with retroauricular extension with preservation of the facial nerve and its branches under general anesthesia. The cystic mass was dissected from the surrounding tissues [Figure 3]. Extirpation was difficult due to its location into the capsule of the parotid. Hemostasis was achieved and closure was done in layers with 3-0 vicryl and 4-0 ethilon. Postoperatively, the recovery was uneventful. Facial nerve function was undisturbed [Figure 4].
Histologically, the biopsy material showed the presence of numerous spindle cells with large wavy nucleus giving Antoni B pattern with microcystic spaces lined by Schwann cells with no evidence of malignancy with the presence of hyalinized blood vessels giving an impression of ancient schwannoma [Figure 5].
Schwannoma is characteristically solitary, encapsulated, and occurring along the course of a peripheral, cranial, or sympathetic nerve. They typically enlarge slowly and vary from firm, solid masses, to fluctuant cysts. Histological appearance is dominated by an encapsulated lesion arising from a nerve and composed of an intimate mixture of spindle cells forming highly cellular Antoni A areas and less cellular, myxoid Antoni B areas. Typically, those lesions that are long-standing may undergo degenerative “ancient” changes dominated by large cystic, myxoid areas with variable bizarre spindle cells and even occasional mitoses. Since the tumor contains cystic areas, ancient schwannoma has been radiologically misdiagnosed as other tumor types. On MRI, the peripheries of ordinary schwannomas yield low-signal intensities on T1-weighted images and high-signal intensities on T2-weighted images, corresponding to the Antoni B region, and low-to-intermediate signal intensities in other areas on T1- and T2-weighted images with strong enhancement by gadolinium contrast medium, a characteristic of the Antoni A regions.
We have presented a rare case of ancient schwannoma of the parotid gland, which is a very rare condition. A careful preoperative clinical and histopathological evaluation and correlation is essential as the ancient schwannoma can deceive the pathologist to malignancy and in turn the surgeon
We would like to thank our Radiology Department and our Department staff (teaching and nonteaching) who helped us in carrying out the prescribed treatment modality and in the publication of this article.
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.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]