A giant benign myoepithelioma of the palate: report of a case

A giant benign myoepithelioma of the palate: report of a case | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report A giant benign myoepithelioma of the palate: report of a case Midion Mapfumo Chidzonga, Blessing Zambuko, Welcome Muungani, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4323796/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Myoepithelioma, previously recognized as a subtype of pleomorphic adenoma, is a rare benign salivary gland neoplasia composed predominantly of myoepithelial cells with variable cellular morphologies: spindle, epitheliod, plasmacytoid, and clear cells. In the World Health Organisation, International Histological Classification of Tumours myoepithelioma is now recognised as a distinct histological entity. Myoepithelial cells are present in salivary glands, breast, larynx, and sweat glands. It is a rare tumor comprising 1-1.5% of all benign and malignant salivary gland tumors, 2.2% of all benign tumors of major salivary glands, and 5.7% of all benign minor salivary gland tumors. It occurs predominantly in the parotid gland and is rare in the minor salivary glands. We are reporting a 44-year-old female who presented with a giant benign myoepithelioma on the palate that grew slowly over 27 years. myoepithelioma myoepithelial cells minor salivary gland palatal tumor plasmacytoid Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 INTRODUCTION Myoepitheliomas [ME] are rare benign neoplasms composed entirely of myoepithelial cells derived from ectoderm-derived contractile cells that exhibit both epithelial and smooth muscle properties [ 1 , 2 , 3 ]. These cells are important in the secretion of saliva. Myoepithelial cells in the salivary glands are located between the basal lamina and the acinar and ductal cells [ 4 ]. Neoplastic myoepithelial cell tumors are also found in other exocrine tissues including lacrimal glands, breast, prostate, sweat glands, vestibular mucosa, labial mucosa, nasopharynx, nasal septum, trachea, larynx, lung, esophagus, and retroperitoneum [ 4 ]. ME is a type of salivary gland tumor once considered a subtype of pleomorphic adenoma until the World Health Organization (WHO) recognized it as a distinct entity in 1991 [ 3 , 5 ]. It exhibits variable cellular morphologies including spindle, epithelioid, plasmacytoid, clear cells, and variable stromal components. ME of the salivary glands is most common in the parotid gland (50%), sublingual gland (33%), and submandibular gland (13%) [ 6 , 7 ]. ME arising from minor salivary glands of the oral cavity are very rare accounting for 1-1.5% of all benign and malignant salivary gland tumors, 2.2% and 5.7% of all benign major and minor salivary gland tumors respectively [ 6 , 7 ]. ME in minor salivary glands of the oral cavity is most common on the palate [ 6 , 7 , 8 ]. Clinically ME presents as an asymptomatic, slowly growing tumor in the fourth and fifth decades of life with no gender predilection [ 4 , 7 , 9 , 10 , 11 ]. However, an analysis of 15 patients by Cuadra et al. showed a 2:1 female predilection [ 4 , 5 , 12 ]. Few cases of palatal myoepithelioma have been reported in children and adolescents [ 9 ]. We present a 44-year-old female who presented with a giant ME on the maxilla/palate that grew slowly over 27 years. CASE REPORT On 18/01/2023 a 44-year-old female attended our Oral and Maxillofacial Surgery clinic with a history of a giant disfiguring slowly growing tumor for the past 27 years. The tumor was on the right maxilla/palate [Figure 1 A&B], lateral and frontal views of the tumor. Figure 1 A Lateral view of the patient at presentation showing the tumor. The tumor started as a small growth and progressively grew over the years. She stated that the tumor was occasionally painful with headaches and bleeding which would resolve without any active intervention. The tumor had now grown to a size that interferes with her speech, feeding, occasionally breathing, and esthetics. Examination showed a giant tumor protruding from the mouth depressing the mandible to the full open mouth position, making it difficult for her to open her mouth further. The mandibular teeth on the right side had been displaced/pushed buccally. The tumor was bony hard protruding from the mouth and abutting the mandible which had been pushed to the mouth open position. The tumor measured approximately 20.0 x 10.0 cm, (Fig. 1 A&B). The tumor literally filled up the oral cavity and was attached to almost three-quarters of the palate sparing a quarter of the right palate. The tumor uninvolved dento-alveolar of the right maxilla was displaced buccally. The left maxilla was infiltrated by the tumor from the incisor region and beyond the maxillary tuberosity and displaced the left zygoma and its arch. The patient could not afford imaging investigations. Endotracheal general anesthesia was administered through a tracheostomy. The Weber-Ferguson incision approach was used to resect the tumor. A bony hard palatal and right maxillary tumor, approximately 20.0 x 10.0 cm, was exposed. The tumor had infiltrated three-quarters of the palate, covering part of the left palate along with the left maxillary dentoalveolar bone from the incisor to the maxillary tuberosity. The posterior end of the tumor spared the soft palate. Superiorly the tumor involved/displaced both maxillary sinuses with medial displacement of the right medial maxillary wall to almost completely obliterating the right nasal cavity. The left maxillary sinus was filled with the tumor with stenosis of the left nasal canal. Both maxillary sinus walls were not spared posteriorly, laterally, and superiorly. Anteriorly the tumor involved the left infraorbital margin extending just lateral to the infraorbital nerve and vessels. On the right side, the infraorbital rim was spared and extended to the level of the infraorbital nerve and vessels. The tumor was encapsulated and shelled out from the oral mucosa to expose normal bone/tumor interface which was resected using osteotomes: hard palate from the soft palate, zygomatic bone, zygomatic arch, and the obliterated sinuses were left intact. Figure 2 A-C shows varied surfaces of the resected tumor masses. Figure 2 A. The resected specimen shows the attached side, a tumor in both maxillary antra and left maxillary teeth. The defect was packed with paraffin gauze soaked in povidone-iodine. Figure 3 , shows the bed of the tumor. The patient tolerated the procedure well. Figure 4 shows the patient 6 weeks postoperatively. However, the mandible had been deformed by the pressure from the tumor hence she could not occlude the right mandible and maxilla. A palatal acrylic obturator was fabricated to close the surgical defect. Macroscopic examination of the surgical specimen showed a tan-grey tissue with bone and teeth together measuring 11.8 cm x 10.5x5.8 cm and weighing 395.8 g. The separate tan-grey tissues with bone were 17.5 x 74.0 x 32. cm and weighed 48.4 g. In total, the tumor tissues weighed 444.2 g. The cut surface of the tumor showed tan-grey to whitish areas and some necrotic areas. Microscopy (Fig. 5 A &B): Several random sections were made from the two samples. The sections from the maxillary mass showed mucosal covering, bone, and respiratory mucosa with a neoplasm comprising sheets, nodules, and rests of epithelioid to spindle cells. The lesional cells possessed eosinophilic hyaline cytoplasm and oval to elongated nuclei with coarse chromatin and inconspicuous nucleoli. The intervening stroma was myxoid and there was lesional necrosis. Focal areas showed the presence of epithelial tubules and cribriform formations. The picture was consistent with a benign ME arising from a salivary gland. There were no cytological features of malignancy. Clinically the patient had no symptoms or signs suggestive of malignancy Figure 5 A & B, show photomicrographs of the specimen, magnification X100, H&E stain. Showing respiratory-type mucosa with underlying myoepithelium comprising irregular nests and cords embedded in a myxoid stroma. Microscopy (Fig. 5 ): Several random sections were made from the two samples. The sections from the maxillary mass showed mucosal covering, bone, and respiratory mucosa with a neoplasm comprising sheets, nodules, and rests of epithelioid to spindle cells. The lesional cells possessed eosinophilic hyaline cytoplasm and oval to elongated nuclei with coarse chromatin and inconspicuous nucleoli. The intervening stroma was myxoid and there was lesional necrosis. Focal areas showed the presence of epithelial tubules and cribriform formations. The picture was consistent with a benign ME arising from a salivary gland. There were no cytological features of malignancy. Clinically the patient had no symptoms or signs suggestive of malignancy. Follow-up visits are difficult in our environment due to high travel costs. Follow-up visits showed marked improvement in the patient’s esthetics, and function. Mouth opening was satisfactory and normal feeding was now possible after the removal of the huge tumor that had filled the oral cavity. DISCUSSION MEs represent less than 1.5% of salivary gland neoplasms. The most common site of occurrence is the parotid gland (40–50%), followed by the minor salivary glands mostly on the hard palate (21%). Among the minor salivary glands ME is most common in the soft and hard palate, however, it constitutes 93% of the minor salivary glands with 7% occurring in the gingiva, cheek, and lips (only three cases in the literature to date) [ 1 ].ME of the salivary glands has no typical clinical features but shares similar features to most other salivary gland tumors and presents as an asymptomatic, slow-growing mass [ 12 , 13 ]. The ME in our case grew slowly over 27 years without any significant symptoms. However, the slow growth resulted in the right mandible being deformed out of occlusion with the right maxilla hence “the mouth open position”, facial disfigurement, and compromised speech and feeding. ME was once considered a variant of pleomorphic adenoma but it is now recognised as a distinct entity. However, the rarity and different phenotypic expression of myoepithelial cells may cause diagnostic difficulties leading to ME being diagnosed as pleomorphic adenoma because of clinical and histological similarities [ 13 ].MEs present with different morphologies: nonmyxoid (solid), myxoid (pleomorphic adenoma-like), reticular (canalicular-like), and mixed [ 6 , 10 ]. The parenchyma ME exhibits various histological features based on the morphological architecture of the neoplastic myoepithelial cells: spindle type, hyaline type, epithelial type, or clear-type tumor cells [ 1 ]. Among these subtypes spindle cell and plasmacytoid variants are most frequent [ 12 , 13 , 14 , 15 ]. The plasmacytoid cell type is most common on the palate. Our case had areas with plasmacytoid and spindle cells. The diagnosis of ME is based on history, physical examination, cytology, and histopathology. Immunohistochemistry is useful for a definitive diagnosis. The tumor cells are highly sensitive to S-100 protein and vimentin [1)] Cytokeratins (AE/AE3, CAM5.2, CK7), calponin, α-SMA, and p63 are focally sensitive diagnostic tools (1, 16–18). Imaging techniques are important in providing information on the location and size of the tumor and its relationship with surrounding structures. In contrast, enhanced CT scan ME appears as a well-defined heterogeneous mildly enhancing soft tissue mass, and on cone beam computed tomography (CBCT) shows a hypodense swelling. No imaging could be done as our patient could not afford the costs involved. Differential diagnosis of ME should include benign tumors (pleomorphic adenoma, schwannoma, neurofibroma, leiomyoma, benign fibrous histiocytoma, and medullary plasmacytoma), malignant salivary gland neoplasia (rhabdomyosarcoma, mucoepidermoid, and myoepithelial carcinoma), mucocele, abscess, and odontogenic cysts. Our case presented as a bony hard tumor suggestive of lesions such as osteoma, ossifying fibroma, and fibrous dysplasia. Kumar et al. reported that 8 cases (3 females and 5 males) of the plasmacytoid cell type on the palate had been reported during the period 1973 to 2017: 3 females and 5 males [ 13 ]. Benign MEs present rare mitosis and absence of nuclear and cellular pleomorphism as well as non-infiltrative growth typical of a benign tumor [ 15 ]. Malignant myoepithelioma exhibits a wide morphological and cytological diversity similar to its benign benign counterpart, ME, and is differentiated by its infiltrative growth pattern, angiolymphatic or perineural invasion, cellular atypia, cellular pleomorphism, cellular necrosis, increased mitotic figures and propensity for metastasis and recurrence [ 19 ] There were no cytologic features of malignancy in our case hence its benign course. The 27-year slow asymptomatic growth is also indicative of a benign tumor. Surgical excision including a margin of normal involved tissue is the mainstay of treatment. This reduces the possibility of recurrence. ME does not present high levels of recurrence. CONCLUSION ME is a rare slow-growing tumor of the salivary glands. A thorough history, clinical examination, radiological examination, and immunochemistry are important to distinguish ME from other salivary gland tumors such as pleomorphic adenoma. Presented is the largest ME with asymptomatic slow growth over 27 years. Wide surgical excision with clear margins reduces recurrence. Declarations Funding: The authors declare that no funds, grants, or other support were received during the preparation of this manuscript. Competing interests: The authors have no relevant financial or non-financial interests to disclose. Author Contributions: All authors contributed to the case report conception and write-up. 1. MM Chidzonga: the case report conception and write-up; first and final draft, surgical management and care of the patient, corresponding author, photography, agreed to submit the case report 2. B Zambuko: histopathology report, photomicrographs, preparation of the first final draft, agreed to the submission of the case report. 3. M. Katiro: surgical management of the case, conception of the report, preparation of the first and final draft, agreed to the submission of the case report. 4. W. Muungani: surgical management and care, preparation of the first final draft, agreed to the submission of the case report. All authors read and approved the final manuscript. ETHICAL APPROVAL: The case report was prepared in line with the principles of the Declaration of Helsinki. Approval for publication was granted by the Joint Parirenyatwa Group of Hospital and the University of Zimbabwe Faculty of Medicine and Health Sciences Research Ethics Committee (JREC). Date: 12 April 2023; Reference: 175/2023 Consent to participate : Informed consent to publish the case report was obtained from the patient. Permission to publish photographs was given by the patient. All possible identification of the patient by the photographs were removed. References Yoshida S, Watanabe A, Akashi Y, Matsuzaka K, Takano M (2023) A case of myoepithelioma in the upper lip. Oral Maxillofac Surg Cases 9. https://doi.org/10.1016/j.omsc.2022.100288 Tachibana H, Ishikawa S, Kikuchi N, Yamakawa M, Hamamoto Y, Lino M (2017) Myoepithelioma of the upper lip. J Dent Sci 12:98–102. https://doi.org/10.1016/j.jds.2013.02.020 Seifert G, Sobin LH, Editors (1991) Histological typing of salivary gland tumors. World Health Organisation International Histological Classification of Tumours. Second Ed. Springer-, Berlin, p 12 Mireles MG, Julian A, Salgado-Chavarria F, Gonzalez GM (2021) Benign myopithelioma of the soft palate; is an unusual clinical entity. BMJ Case Rep 14:e240384. .https://doi.org/10.1136/bcr-2020-240384 Wang J-Q, Debg R-X, Liu H et al (2022) Malignant myoepithelioma of the head and neck: demographics, clinicopathological characteristics, treatment, and prognosis. Front Oncol 12:754967. https://doi.org/10.3389/fonc.2022.754967 Dardick I, Thomas MJ, van Nostrand AW (1989) Myoepithelioma new concepts of histology and classification: a light and electron microscopic study. Ultrastruct Pathol 13:187–224. htpps://doi.org/10.3109/01913128109057442 Yadav AK, Nadarajah J, Chandrashekhara J et al (2013) Myoepithelioma of the soft palate: a case report. Case Reports in Otolaryngology. https://doi.10.1155/2013/642806 Cardesa A, Alos L Myoepithelioma in Pathology and Genetics of Head and Neck Tumors, Barnes L, Eveson JW,Reichart P, Sidransky D, Eds, World Health Organization of Tumors, pp.259–260,IARC Press, Lyon, France,2005 Hiwatashi A, Matsumoto S, Kamoi H, et.al (2000) Imaging features of myoepithelioma arising from the hard palate: a case report. Acta Raddiologica 41:417–419. htpps://doi.org/10.1080/028418500012734539 Patankar S, Sharma R, Patankar A, Kulkami V (2021) Rare case of giant myoepithelioma in minor salivary glands of the palate in a 9-year-old child. Natl J Maxillofac Surg 12:284–288. .https://doi:10.4103/njms.NJMS_16_19 Karthik RS, Sivakumar JS, Cholan R, Myoepithelioma et al (2015) J Pharm Bioallied Sci 7(Suppl 2):S779. htpps://doi.org/10.4103/0975-7406.163580 . S781 Tachibana H, Ishikawa S, Kikuchi N et al (2017) Myoepithelioma of the upper lip. J Dent Sci 12:98–102. https://doi.org/10.1016/j.jds.2013.02 .020.Epub 2013 Apr 11 Mughal A, Danish H, Hassan S et al (2022) Myoepithelioma of the parotid gland: a case report and literature review. Indian J Otolaryngol Head Neck Surg 74:6087–6090. htpps://doi.org/10.1007/s12070-021-02763-x Epub 2021 Jul 9 Barca I, Novembre D, Cordaro R et al (2020) Myoepithelioma of the parotid gland: a case report with review of the literature. Oral Maxillofac Cases 6. htpps:/doi.org/10.1016//j.omsc.2019.100131 Kumar M, Acharya S, Pai K et al (2017) Unusual neoplasm on the hard palate of a child: a case report. J Med Case Rep 149 11:149. https://doi.org/10.1186/s13256-017-1321-4 Maffi-Berthier L, Le Pelletier F, Ejeil A-L (2018) Benign myoepithelioma of the hard palate: a clinical and histological diagnostic challenge: a case report and literature review. J Oral Med Surg 24:81–88. htpps://doi.org/10.1051/mbcb/2017040 Advani K, Diwan N, Pai A et al (2017) Myepithelioma of the hard palate: a rare case report. Int Oral Care Res 5:260–263 Park TH, Seo SW (2011) Diagnostic challenges of myoepithelial arising from a minor salivary gland. J Oral Maxillofac Surg 69:2830–2832. .htpps://doi.org/10.1016/j.joms,2011.03 . 003.Epuhb 2011 Jul 22 Cuadra-Zelaya T, Quezada-Rivera D, Tapia- Vazquez JL et al (2007) Plasmacytoid myoepithelioma of the palate: report of one case and review of the literature. Med oral patol. oral cir. buccal (Internet) vol 12 no 8 dic 1; 12(8):E552-5 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4323796","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":297559557,"identity":"5965c32f-a1c7-4607-9a83-8cc348f64bce","order_by":0,"name":"Midion Mapfumo Chidzonga","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA4ElEQVRIiWNgGAWjYJACZgYDZgjrAwNDAmH1bEhaGGcQr4UBooWZhxgtuvO7Ez8XFFjb80u3X/xs22aXx8/ewPjhYw5uLWbHeDdLzzBIZ5acc6ZYOrctuViy5wCz5MxteLVsY+YxOMxmcCMnAaiFOXHDjQQ2Zl4itPAAtST/tmyrJ16LhMGN9GPSjG2HidGSu1maxyDdQHJGDptlz7njiTN7Djbj98vhsxs/8/wBhphE+uMbP8qqE/vZmw9++IhHCxLgMWBgZAMxGBuIUg8E7A8YGP4Qq3gUjIJRMApGEgAAge1PQBdeex8AAAAASUVORK5CYII=","orcid":"","institution":"Faculty of Medicine and Health Sciences,University of Zimbabwe","correspondingAuthor":true,"prefix":"","firstName":"Midion","middleName":"Mapfumo","lastName":"Chidzonga","suffix":""},{"id":297559558,"identity":"fda48fcb-df2a-4457-95e0-1b3ea58a5d13","order_by":1,"name":"Blessing Zambuko","email":"","orcid":"","institution":"Faculty of Medicine and Health Sciences,University of Zimbabwe","correspondingAuthor":false,"prefix":"","firstName":"Blessing","middleName":"","lastName":"Zambuko","suffix":""},{"id":297559559,"identity":"70522414-ab54-4612-a5f7-eeefb3f60aab","order_by":2,"name":"Welcome Muungani","email":"","orcid":"","institution":"Faculty of Medicine and Health Sciences,University of Zimbabwe","correspondingAuthor":false,"prefix":"","firstName":"Welcome","middleName":"","lastName":"Muungani","suffix":""},{"id":297559560,"identity":"3b7a497b-bab8-4ab7-8ce0-5ed1a2d96f7c","order_by":3,"name":"Munyaradzi Phillip Katiro","email":"","orcid":"","institution":"Faculty of Medicine and Health Sciences,University of Zimbabwe","correspondingAuthor":false,"prefix":"","firstName":"Munyaradzi","middleName":"Phillip","lastName":"Katiro","suffix":""}],"badges":[],"createdAt":"2024-04-25 11:28:52","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4323796/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4323796/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":55809270,"identity":"d0ba0f5f-25e1-40fe-a6e9-238a4e8e2392","added_by":"auto","created_at":"2024-05-03 15:40:10","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1816415,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eA:\u003c/strong\u003e Lateral view of the patient at presentation showing the tumor.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eB.\u003c/strong\u003e Frontal view showing the intraoral appearance of the tumor\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-4323796/v1/1c652721a21455646280b19c.png"},{"id":55807721,"identity":"81e2eb19-4d21-4ed5-bd1b-0f0728c642b9","added_by":"auto","created_at":"2024-05-03 15:32:10","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":4794282,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eA\u003c/strong\u003e. The resected specimen shows the attached side, a tumor in both maxillary antra and left maxillary teeth.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eB. \u003c/strong\u003eShows the oral aspect of the tumor protruding from the mouth\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eC.\u003c/strong\u003e Showing the superior aspect of the tumor along with fragments of the tumor\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-4323796/v1/c18fab222ad145ba8bdaad22.png"},{"id":55807717,"identity":"d2540320-63b8-4e4e-bc86-00626fac55f5","added_by":"auto","created_at":"2024-05-03 15:32:10","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":345537,"visible":true,"origin":"","legend":"\u003cp\u003eIntraoperative view showing the bed of the tumor.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-4323796/v1/192de087542ed1210e5d78b6.png"},{"id":55807719,"identity":"f62d83e6-d09a-4816-a874-ba31df2f9756","added_by":"auto","created_at":"2024-05-03 15:32:10","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":4493,"visible":true,"origin":"","legend":"\u003cp\u003eLegend not included with this version\u003c/p\u003e","description":"","filename":"fig.png","url":"https://assets-eu.researchsquare.com/files/rs-4323796/v1/5493fcd97d7bad5a70d52f20.png"},{"id":55807720,"identity":"060f1438-5824-461d-822e-de57746c9cfc","added_by":"auto","created_at":"2024-05-03 15:32:10","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":4016302,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eA.\u003c/strong\u003ePhotomicrograph showing bone respiratory type mucosa with a neoplasm comprising sheets, nodules and rests of epithelioid to spindle cells, irregular nests and cords in a myxoid stroma.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eB. \u003c/strong\u003ePhotomicrograph showing bone respiratory type mucosa with a neoplasm comprising sheets, nodules, and rests of epithelioid to spindle cells, irregular nests, and cords in a myxoid stroma.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-4323796/v1/f2c27e8f922fe13ecbfc51ba.png"},{"id":55878493,"identity":"d1302631-b408-4cbc-b8d6-16ccd8be651a","added_by":"auto","created_at":"2024-05-05 15:49:57","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2853989,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4323796/v1/7c0c019c-f80d-45d4-a2da-8fded5959b13.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eA giant benign myoepithelioma of the palate: report of a case\u003c/p\u003e","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eMyoepitheliomas [ME] are rare benign neoplasms composed entirely of myoepithelial cells derived from ectoderm-derived contractile cells that exhibit both epithelial and smooth muscle properties [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. These cells are important in the secretion of saliva. Myoepithelial cells in the salivary glands are located between the basal lamina and the acinar and ductal cells [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Neoplastic myoepithelial cell tumors are also found in other exocrine tissues including lacrimal glands, breast, prostate, sweat glands, vestibular mucosa, labial mucosa, nasopharynx, nasal septum, trachea, larynx, lung, esophagus, and retroperitoneum [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. ME is a type of salivary gland tumor once considered a subtype of pleomorphic adenoma until the World Health Organization (WHO) recognized it as a distinct entity in 1991 [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. It exhibits variable cellular morphologies including spindle, epithelioid, plasmacytoid, clear cells, and variable stromal components. ME of the salivary glands is most common in the parotid gland (50%), sublingual gland (33%), and submandibular gland (13%) [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. ME arising from minor salivary glands of the oral cavity are very rare accounting for 1-1.5% of all benign and malignant salivary gland tumors, 2.2% and 5.7% of all benign major and minor salivary gland tumors respectively [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. ME in minor salivary glands of the oral cavity is most common on the palate [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Clinically ME presents as an asymptomatic, slowly growing tumor in the fourth and fifth decades of life with no gender predilection [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. However, an analysis of 15 patients by Cuadra et al. showed a 2:1 female predilection [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Few cases of palatal myoepithelioma have been reported in children and adolescents [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eWe present a 44-year-old female who presented with a giant ME on the maxilla/palate that grew slowly over 27 years.\u003c/p\u003e"},{"header":"CASE REPORT","content":"\u003cp\u003eOn 18/01/2023 a 44-year-old female attended our Oral and Maxillofacial Surgery clinic with a history of a giant disfiguring slowly growing tumor for the past 27 years. The tumor was on the right maxilla/palate [Figure \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eA\u0026amp;B], lateral and frontal views of the tumor.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eA\u003c/strong\u003e \u003cp\u003eLateral view of the patient at presentation showing the tumor.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe tumor started as a small growth and progressively grew over the years. She stated that the tumor was occasionally painful with headaches and bleeding which would resolve without any active intervention. The tumor had now grown to a size that interferes with her speech, feeding, occasionally breathing, and esthetics. Examination showed a giant tumor protruding from the mouth depressing the mandible to the full open mouth position, making it difficult for her to open her mouth further. The mandibular teeth on the right side had been displaced/pushed buccally. The tumor was bony hard protruding from the mouth and abutting the mandible which had been pushed to the mouth open position. The tumor measured approximately 20.0 x 10.0 cm, (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eA\u0026amp;B). The tumor literally filled up the oral cavity and was attached to almost three-quarters of the palate sparing a quarter of the right palate. The tumor uninvolved dento-alveolar of the right maxilla was displaced buccally. The left maxilla was infiltrated by the tumor from the incisor region and beyond the maxillary tuberosity and displaced the left zygoma and its arch. The patient could not afford imaging investigations.\u003c/p\u003e \u003cp\u003eEndotracheal general anesthesia was administered through a tracheostomy. The Weber-Ferguson incision approach was used to resect the tumor. A bony hard palatal and right maxillary tumor, approximately 20.0 x 10.0 cm, was exposed. The tumor had infiltrated three-quarters of the palate, covering part of the left palate along with the left maxillary dentoalveolar bone from the incisor to the maxillary tuberosity. The posterior end of the tumor spared the soft palate. Superiorly the tumor involved/displaced both maxillary sinuses with medial displacement of the right medial maxillary wall to almost completely obliterating the right nasal cavity. The left maxillary sinus was filled with the tumor with stenosis of the left nasal canal. Both maxillary sinus walls were not spared posteriorly, laterally, and superiorly. Anteriorly the tumor involved the left infraorbital margin extending just lateral to the infraorbital nerve and vessels. On the right side, the infraorbital rim was spared and extended to the level of the infraorbital nerve and vessels.\u003c/p\u003e \u003cp\u003eThe tumor was encapsulated and shelled out from the oral mucosa to expose normal bone/tumor interface which was resected using osteotomes: hard palate from the soft palate, zygomatic bone, zygomatic arch, and the obliterated sinuses were left intact. Figure\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e2\u003c/span\u003eA-C shows varied surfaces of the resected tumor masses.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e2\u003c/span\u003eA. The resected specimen shows the attached side, a tumor in both maxillary antra and left maxillary teeth.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe defect was packed with paraffin gauze soaked in povidone-iodine. Figure\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e3\u003c/span\u003e, shows the bed of the tumor. The patient tolerated the procedure well. Figure\u0026nbsp;4 shows the patient 6 weeks postoperatively. However, the mandible had been deformed by the pressure from the tumor hence she could not occlude the right mandible and maxilla. A palatal acrylic obturator was fabricated to close the surgical defect.\u003c/p\u003e \u003cp\u003eMacroscopic examination of the surgical specimen showed a tan-grey tissue with bone and teeth together measuring 11.8 cm x 10.5x5.8 cm and weighing 395.8 g. The separate tan-grey tissues with bone were 17.5 x 74.0 x 32. cm and weighed 48.4 g. In total, the tumor tissues weighed 444.2 g. The cut surface of the tumor showed tan-grey to whitish areas and some necrotic areas.\u003c/p\u003e \u003cp\u003eMicroscopy (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e5\u003c/span\u003eA \u0026amp;B): Several random sections were made from the two samples. The sections from the maxillary mass showed mucosal covering, bone, and respiratory mucosa with a neoplasm comprising sheets, nodules, and rests of epithelioid to spindle cells. The lesional cells possessed eosinophilic hyaline cytoplasm and oval to elongated nuclei with coarse chromatin and inconspicuous nucleoli. The intervening stroma was myxoid and there was lesional necrosis. Focal areas showed the presence of epithelial tubules and cribriform formations. The picture was consistent with a benign ME arising from a salivary gland. There were no cytological features of malignancy. Clinically the patient had no symptoms or signs suggestive of malignancy\u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e5\u003c/span\u003eA \u0026amp; B, show photomicrographs of the specimen, magnification X100, H\u0026amp;E stain. Showing respiratory-type mucosa with underlying myoepithelium comprising irregular nests and cords embedded in a myxoid stroma.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eMicroscopy (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e5\u003c/span\u003e): Several random sections were made from the two samples. The sections from the maxillary mass showed mucosal covering, bone, and respiratory mucosa with a neoplasm comprising sheets, nodules, and rests of epithelioid to spindle cells. The lesional cells possessed eosinophilic hyaline cytoplasm and oval to elongated nuclei with coarse chromatin and inconspicuous nucleoli. The intervening stroma was myxoid and there was lesional necrosis. Focal areas showed the presence of epithelial tubules and cribriform formations. The picture was consistent with a benign ME arising from a salivary gland. There were no cytological features of malignancy. Clinically the patient had no symptoms or signs suggestive of malignancy.\u003c/p\u003e \u003cp\u003eFollow-up visits are difficult in our environment due to high travel costs. Follow-up visits showed marked improvement in the patient\u0026rsquo;s esthetics, and function. Mouth opening was satisfactory and normal feeding was now possible after the removal of the huge tumor that had filled the oral cavity.\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eMEs represent less than 1.5% of salivary gland neoplasms. The most common site of occurrence is the parotid gland (40\u0026ndash;50%), followed by the minor salivary glands mostly on the hard palate (21%). Among the minor salivary glands ME is most common in the soft and hard palate, however, it constitutes 93% of the minor salivary glands with 7% occurring in the gingiva, cheek, and lips (only three cases in the literature to date) [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e].ME of the salivary glands has no typical clinical features but shares similar features to most other salivary gland tumors and presents as an asymptomatic, slow-growing mass [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. The ME in our case grew slowly over 27 years without any significant symptoms. However, the slow growth resulted in the right mandible being deformed out of occlusion with the right maxilla hence \u0026ldquo;the mouth open position\u0026rdquo;, facial disfigurement, and compromised speech and feeding.\u003c/p\u003e \u003cp\u003eME was once considered a variant of pleomorphic adenoma but it is now recognised as a distinct entity. However, the rarity and different phenotypic expression of myoepithelial cells may cause diagnostic difficulties leading to ME being diagnosed as pleomorphic adenoma because of clinical and histological similarities [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].MEs present with different morphologies: nonmyxoid (solid), myxoid (pleomorphic adenoma-like), reticular (canalicular-like), and mixed [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. The parenchyma ME exhibits various histological features based on the morphological architecture of the neoplastic myoepithelial cells: spindle type, hyaline type, epithelial type, or clear-type tumor cells [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Among these subtypes spindle cell and plasmacytoid variants are most frequent [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. The plasmacytoid cell type is most common on the palate. Our case had areas with plasmacytoid and spindle cells. The diagnosis of ME is based on history, physical examination, cytology, and histopathology. Immunohistochemistry is useful for a definitive diagnosis. The tumor cells are highly sensitive to S-100 protein and vimentin [1)] Cytokeratins (AE/AE3, CAM5.2, CK7), calponin, α-SMA, and p63 are focally sensitive diagnostic tools (1, 16\u0026ndash;18). Imaging techniques are important in providing information on the location and size of the tumor and its relationship with surrounding structures. In contrast, enhanced CT scan ME appears as a well-defined heterogeneous mildly enhancing soft tissue mass, and on cone beam computed tomography (CBCT) shows a hypodense swelling. No imaging could be done as our patient could not afford the costs involved.\u003c/p\u003e \u003cp\u003eDifferential diagnosis of ME should include benign tumors (pleomorphic adenoma, schwannoma, neurofibroma, leiomyoma, benign fibrous histiocytoma, and medullary plasmacytoma), malignant salivary gland neoplasia (rhabdomyosarcoma, mucoepidermoid, and myoepithelial carcinoma), mucocele, abscess, and odontogenic cysts. Our case presented as a bony hard tumor suggestive of lesions such as osteoma, ossifying fibroma, and fibrous dysplasia.\u003c/p\u003e \u003cp\u003eKumar et al. reported that 8 cases (3 females and 5 males) of the plasmacytoid cell type on the palate had been reported during the period 1973 to 2017: 3 females and 5 males [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Benign MEs present rare mitosis and absence of nuclear and cellular pleomorphism as well as non-infiltrative growth typical of a benign tumor [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Malignant myoepithelioma exhibits a wide morphological and cytological diversity similar to its benign benign counterpart, ME, and is differentiated by its infiltrative growth pattern, angiolymphatic or perineural invasion, cellular atypia, cellular pleomorphism, cellular necrosis, increased mitotic figures and propensity for metastasis and recurrence [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e] There were no cytologic features of malignancy in our case hence its benign course. The 27-year slow asymptomatic growth is also indicative of a benign tumor.\u003c/p\u003e \u003cp\u003eSurgical excision including a margin of normal involved tissue is the mainstay of treatment. This reduces the possibility of recurrence. ME does not present high levels of recurrence.\u003c/p\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eME is a rare slow-growing tumor of the salivary glands. A thorough history, clinical examination, radiological examination, and immunochemistry are important to distinguish ME from other salivary gland tumors such as pleomorphic adenoma. Presented is the largest ME with asymptomatic slow growth over 27 years. Wide surgical excision with clear margins reduces recurrence.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003eThe authors declare that no funds, grants, or other support were received during the preparation of this manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests:\u003c/strong\u003e The authors have no relevant financial or non-financial interests to disclose.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contributions:\u003c/strong\u003e All authors contributed to the case report conception and write-up.\u003c/p\u003e\n\u003cp\u003e1. MM Chidzonga: the case report conception and write-up; first and final draft, surgical management and care of the patient, corresponding author, photography, agreed to submit the case report\u003c/p\u003e\n\u003cp\u003e2. B Zambuko: histopathology report, photomicrographs, preparation of the first final draft, agreed to the submission of the case report.\u003c/p\u003e\n\u003cp\u003e3. M. Katiro: surgical management of the case, conception of the report, preparation of the first and final draft, agreed to the submission of the case report.\u003c/p\u003e\n\u003cp\u003e4. W. Muungani: surgical management and care, preparation of the first final draft, agreed to the submission of the case report.\u003c/p\u003e\n\u003cp\u003eAll authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eETHICAL APPROVAL:\u003c/strong\u003e The case report was prepared in line with the principles of the Declaration of Helsinki. Approval for publication was granted by the Joint Parirenyatwa Group of Hospital and the University of Zimbabwe Faculty of Medicine and Health Sciences Research Ethics Committee (JREC).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDate: 12 April 2023; Reference: 175/2023\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to participate\u003c/strong\u003e: Informed consent to publish the case report was obtained from the patient. Permission to publish photographs was given by the patient. All possible identification of the patient by the photographs were removed.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eYoshida S, Watanabe A, Akashi Y, Matsuzaka K, Takano M (2023) A case of myoepithelioma in the upper lip. Oral Maxillofac Surg Cases 9. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.omsc.2022.100288\u003c/span\u003e\u003cspan address=\"10.1016/j.omsc.2022.100288\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTachibana H, Ishikawa S, Kikuchi N, Yamakawa M, Hamamoto Y, Lino M (2017) Myoepithelioma of the upper lip. J Dent Sci 12:98\u0026ndash;102. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.jds.2013.02.020\u003c/span\u003e\u003cspan address=\"10.1016/j.jds.2013.02.020\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSeifert G, Sobin LH, Editors (1991) Histological typing of salivary gland tumors. World Health Organisation International Histological Classification of Tumours. Second Ed. Springer-, Berlin, p 12\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMireles MG, Julian A, Salgado-Chavarria F, Gonzalez GM (2021) Benign myopithelioma of the soft palate; is an unusual clinical entity. BMJ Case Rep 14:e240384. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e.https://doi.org/10.1136/bcr-2020-240384\u003c/span\u003e\u003cspan address=\".10.1136/bcr-2020-240384\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWang J-Q, Debg R-X, Liu H et al (2022) Malignant myoepithelioma of the head and neck: demographics, clinicopathological characteristics, treatment, and prognosis. Front Oncol 12:754967. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.3389/fonc.2022.754967\u003c/span\u003e\u003cspan address=\"10.3389/fonc.2022.754967\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDardick I, Thomas MJ, van Nostrand AW (1989) Myoepithelioma new concepts of histology and classification: a light and electron microscopic study. Ultrastruct Pathol 13:187\u0026ndash;224. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehtpps://doi.org/10.3109/01913128109057442\u003c/span\u003e\u003cspan address=\"htpps://10.3109/01913128109057442\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYadav AK, Nadarajah J, Chandrashekhara J et al (2013) Myoepithelioma of the soft palate: a case report. Case Reports in Otolaryngology. https://doi.10.1155/2013/642806\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCardesa A, Alos L Myoepithelioma in Pathology and Genetics of Head and Neck Tumors, Barnes L, Eveson JW,Reichart P, Sidransky D, Eds, World Health Organization of Tumors, pp.259\u0026ndash;260,IARC Press, Lyon, France,2005\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHiwatashi A, Matsumoto S, Kamoi H, et.al (2000) Imaging features of myoepithelioma arising from the hard palate: a case report. Acta Raddiologica 41:417\u0026ndash;419. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehtpps://doi.org/10.1080/028418500012734539\u003c/span\u003e\u003cspan address=\"htpps://10.1080/028418500012734539\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePatankar S, Sharma R, Patankar A, Kulkami V (2021) Rare case of giant myoepithelioma in minor salivary glands of the palate in a 9-year-old child. Natl J Maxillofac Surg 12:284\u0026ndash;288. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e.https://doi:10.4103/njms.NJMS_16_19\u003c/span\u003e\u003cspan address=\".https://doi:10.4103/njms.NJMS_16_19\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKarthik RS, Sivakumar JS, Cholan R, Myoepithelioma et al (2015) J Pharm Bioallied Sci 7(Suppl 2):S779. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehtpps://doi.org/10.4103/0975-7406.163580\u003c/span\u003e\u003cspan address=\"htpps://10.4103/0975-7406.163580\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. S781\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTachibana H, Ishikawa S, Kikuchi N et al (2017) Myoepithelioma of the upper lip. J Dent Sci 12:98\u0026ndash;102. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.jds.2013.02\u003c/span\u003e\u003cspan address=\"10.1016/j.jds.2013.02\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.020.Epub 2013 Apr 11\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMughal A, Danish H, Hassan S et al (2022) Myoepithelioma of the parotid gland: a case report and literature review. Indian J Otolaryngol Head Neck Surg 74:6087\u0026ndash;6090. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehtpps://doi.org/10.1007/s12070-021-02763-x\u003c/span\u003e\u003cspan address=\"htpps://10.1007/s12070-021-02763-x\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003eEpub 2021 Jul 9\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBarca I, Novembre D, Cordaro R et al (2020) Myoepithelioma of the parotid gland: a case report with review of the literature. Oral Maxillofac Cases 6. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehtpps:/doi.org/10.1016//j.omsc.2019.100131\u003c/span\u003e\u003cspan address=\"htpps:/10.1016//j.omsc.2019.100131\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKumar M, Acharya S, Pai K et al (2017) Unusual neoplasm on the hard palate of a child: a case report. J Med Case Rep 149 11:149. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1186/s13256-017-1321-4\u003c/span\u003e\u003cspan address=\"10.1186/s13256-017-1321-4\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMaffi-Berthier L, Le Pelletier F, Ejeil A-L (2018) Benign myoepithelioma of the hard palate: a clinical and histological diagnostic challenge: a case report and literature review. J Oral Med Surg 24:81\u0026ndash;88. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehtpps://doi.org/10.1051/mbcb/2017040\u003c/span\u003e\u003cspan address=\"htpps://10.1051/mbcb/2017040\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAdvani K, Diwan N, Pai A et al (2017) Myepithelioma of the hard palate: a rare case report. Int Oral Care Res 5:260\u0026ndash;263\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePark TH, Seo SW (2011) Diagnostic challenges of myoepithelial arising from a minor salivary gland. J Oral Maxillofac Surg 69:2830\u0026ndash;2832. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e.htpps://doi.org/10.1016/j.joms,2011.03\u003c/span\u003e\u003cspan address=\".htpps://10.1016/j.joms,2011.03\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. 003.Epuhb 2011 Jul 22\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCuadra-Zelaya T, Quezada-Rivera D, Tapia- Vazquez JL et al (2007) Plasmacytoid myoepithelioma of the palate: report of one case and review of the literature. Med oral patol. oral cir. buccal (Internet) vol 12 no 8 dic 1; 12(8):E552-5\u003c/span\u003e\u003c/li\u003e "}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"myoepithelioma, myoepithelial cells, minor salivary gland, palatal tumor, plasmacytoid","lastPublishedDoi":"10.21203/rs.3.rs-4323796/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4323796/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eMyoepithelioma, previously recognized as a subtype of pleomorphic adenoma, is a rare benign salivary gland neoplasia composed predominantly of myoepithelial cells with variable cellular morphologies: spindle, epitheliod, plasmacytoid, and clear cells. In the World Health Organisation, International Histological Classification of Tumours myoepithelioma is now recognised as a distinct histological entity. Myoepithelial cells are present in salivary glands, breast, larynx, and sweat glands. It is a rare tumor comprising 1-1.5% of all benign and malignant salivary gland tumors, 2.2% of all benign tumors of major salivary glands, and 5.7% of all benign minor salivary gland tumors. It occurs predominantly in the parotid gland and is rare in the minor salivary glands. We are reporting a 44-year-old female who presented with a giant benign myoepithelioma on the palate that grew slowly over 27 years.\u003c/p\u003e","manuscriptTitle":"A giant benign myoepithelioma of the palate: report of a case","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-05-03 15:32:05","doi":"10.21203/rs.3.rs-4323796/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"65af9227-71a6-496a-b0a2-127afb82236c","owner":[],"postedDate":"May 3rd, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-05-05T15:41:46+00:00","versionOfRecord":[],"versionCreatedAt":"2024-05-03 15:32:05","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4323796","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4323796","identity":"rs-4323796","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}