CLINICAL DENTISTRY AND RESEARCH 2017; 41(3): 132-138 Case Report

CorrespondenceEzgi Ergezen DDS

Department of Oral & Maxillofacial Surgery,

Faculty of Dentistry,

Hacettepe University

06100, Sıhhiye, Ankara, Turkey

Phone: 03130532220

GSM :5377415292

E-mail: ezgiergezen@gmail.com

Selen Adiloğlu DDS, PhD Department of Oral & Maxillofacial Surgery,

Faculty of Dentistry, Hacettepe University,

Ankara,Turkey

Ezgi Ergezen, DDS Research Asistant, Department of Oral & Maxillofacial Surgery,

Faculty of Dentistry, Hacettepe University,

Ankara,Turkey

Alper Aktaş, DDS, PhD Associate Professor, Department of Oral & Maxillofacial Surgery,

Faculty of Dentistry, Hacettepe University,

Ankara,Turkey

Canseda Avağ, DDS Research Asistant, Department of Oral & Maxillofacial Surgery,

Faculty of Dentistry, Hacettepe University,

Ankara,Turkey

Duygu Uçar, DDS Research Asistant, Department of Oral & Maxillofacial Surgery,

Faculty of Dentistry, Hacettepe University,

Ankara,Turkey

MUCOEPIDERMOID CARCINOMA LOCALIZED IN PALATE: 3 CASES AND REVIEW OF THE LITERATURE

ABSTRACT

The aim of this case report is to present the clinical and histopathological aspects of the 3 mucoepidermoid carcinoma cases referred to our clinic, together with the review of the latest literatures. Total of 3 female patients who were 35, 48 and 49-year-old referred to our clinic between April-October 2015 with a complaint of asymptomatic swelling of the palate. Lesions were present for almost a year. Excisional and incisional biopsies were performed. Histopathological evaluation revealed low-grade mucoepidermoid carcinoma for all the lesions that biopsy was carried out. Mucoepidermoid carcinoma should be considered in existence of soft, slow-growing, painless lumps of the palate for differential diagnosis and early biopsy should be performed for such lesions as it may easily be misdiagnosed.

Keywords: Malignant Epithelial Tumors, Mucoepidermoid

Carcinoma

Submitted for Publication: 07.26.2017

Accepted for Publication : 11.29.2017

Clin Dent Res 2017: 41(3): 132-138

132

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CLINICAL DENTISTRY AND RESEARCH 2017; 41(3): 132-138 Olgu Bildirimi

Sorumlu YazarEzgi Ergezen

Hacettepe Üniversitesi,

Diş hekimliği Fakültesi,

Ağız Diş ve Çene Hastalıkları Cerrahisi,

06100 Sıhhiye Ankara, Türkiye

Selen AdiloğluDr., Hacettepe Üniversitesi, Diş hekimliği Fakültesi,

Ağız Diş ve Çene Hastalıkları Cerrahisi,

Ankara, Türkiye

Ezgi ErgezenArş. Gör., Hacettepe Üniversitesi, Diş hekimliği Fakültesi,

Ağız Diş ve Çene Hastalıkları Cerrahisi,

Ankara, Türkiye

Alper AktaşDoç. Dr., Hacettepe Üniversitesi, Diş hekimliği Fakültesi,

Ağız Diş ve Çene Hastalıkları Cerrahisi

Ankara, Türkiye

Canseda Avağ Arş. Gör., Hacettepe Üniversitesi, Diş hekimliği Fakültesi,

Ağız Diş ve Çene Hastalıkları Cerrahisi,

Ankara, Türkiye

Duygu UçarArş. Gör., Hacettepe Üniversitesi, Diş hekimliği Fakültesi,

Ağız Diş ve Çene Hastalıkları Cerrahisi,

Ankara, Türkiye

PALATINADA LOKALIZE MUKOEPIDERMOID KARSİNOMA: 3 VAKA SUNUMU VE LİTERATÜR DERLEMESİ

ÖZ

Bu derlemenin amacı mukoepidermoid karsinomanın klinik ve histopatolojik özelliklerinin değerlendirilmesi ile 3 mukoepidermoid karsinom vakasının sunulmasıdır. Nisan-Ekim 2015 tarihleri arasında kliniğimize palatal bölgede ağrısız yavaş büyüyen şişlik şikayeti ile 35, 48 ve 49 yaşlarında 3 kadın hasta başvurdu. Ortalama 1 yıldır mevcut olan lezyonların bir tanesine boyutunun küçük olması nedeni ile eksizyonel, diğer iki vakaya insizyonel biyopsi yapıldı. Histopatolojik inceleme sonucunda tüm lezyonlar düşük dereceli mukoepidermoid karsinom olarak değerlendirildi. Bu vaka raporunda incelenen 3 hasta, literatürde mevcut olan mukoepidermoid karsinoma verileri ile uyumludur. Palatinal bölgede mevcut ağrısız şişliklerde, minör tükrük bezi kaynaklı mukoepidermoid karsinoma ayırıcı tanısının akılda tutulması ve erken dönemde biyopsi yapılması hastaların doğru yönlendirilmesi açısından önemlidir.

Anahtar Kelimeler: Malign Epitelyal Tümörler,

Mukoepidermoid Karsinoma

Yayın Başvuru Tarihi : 26.07.2017

Yayına Kabul Tarihi : 29.11.2017

Clin Dent Res 2017: 41(3): 132-138

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INTRODUCTION

Mucoepidermoid carcinoma (MEC) is a malignant epithelial neoplasm derived from mucous epithelial cells.1 Mucoepidermoid carcinoma is the most common malignant salivary gland tumor generally located in parotid gland and minor salivary glands.2 The etiology still remains unclear. However, it is shown that the translocation of the specific (11;19)(q21;p13) chromosomes is related with the occurrence of MEC.3,4

Lesions are generally present as smooth surfaced, soft, slow growing painless swellings.5,6 Clinically, it is similar to pleomorphic adenoma.5 Musin can be seen draining through a sinus tract in some cases.7 Pain and facial nerve paresthesia may occur in high grade tumors.5

MEC is histopathologically classified as low, medium and high-grade tumors that affect the prognosis of disease. High-grade tumors are more aggressive and have worse prognosis than low- grade tumors.8

In this case report, it is presented that 3 different patients with asymptomatic expansion localized in the palate are evaluated clinically and histopathologically.

CASE REPORTS

Case 1

35-year-old female patient referred to our clinic in May 2015 with the complaint of palatal swelling localized in the premolar molar region extending to the soft palate. The lesion was slow growing, presented approximately for a year with no symptoms. Clinically the surface of the lesion was not ulcerated and appeared to be bluish-purple (Figure1A). The adjacent teeth were vital and asymptomatic.

Figure 1. Case 1 A. Preoperative clinical appearance, B. Preoperative radiograph, C., D. Palatal destruction related to the lesion seen at CBCT images, E. Postoperative CBCT image after hemimaxillectomy.

Radiological examination with ortopantomograph did not show any sign of destruction (Figure 1B). Cone beam computed tomography (CBCT) images showed minimal destructions of palatal bone. (Figure1C-1D).The aspiration biopsy was applied and it was negative as the lesion was solid in nature. Biopsy was planned, by the provisional diagnosis as pleomorphic adenoma. A wedge-shaped incisional biopsy of the lesion was performed, where the lesion was most significant. Histopathological evaluation showed low-grade MEC. The borders of the specimen, which is excised, had tumor cells. Patient referred to department of otorhinolaryngology for further diagnosis and treatment. Hemimaxillectomy was applied and radiotherapy was planned post operatively (Figure 1E). After the healing period, reconstruction was made with an

obturator by department of prosthesis.

Case 2

48-year-old female patient referred to our clinic in

September 2015 with a palatal swelling localized in

the premolar region. The surface of the lesion was not

ulcerated, it was asymptomatic and the adjacent teeth were

vital. Radiological examination with ortopantomograph did

not show any sign of destruction (Figure 2A). The aspiration

biopsy was applied and it was negative and lesion was small

enough for excisional biopsy, sulcular incision was started

from 1st premolar followed by the elevation of full thickness

flap (Figure 2B) then the lesion was excised by blunt

dissection (Figure 2C). Histopathological evaluation showed

low-grade MEC. Patient referred to otorhinolaryngology

department for further diagnosis and treatment. The local

excision was performed and no additional treatment was

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MucoepiderMoid carcinoMa

Figure 2. Case 2 A. Preoperative radiograph B. intraoperative appearance C. Excised lesion

Figure 3. Case 3 A. Preoperative radiograph B. CBCT image of the lesion without any bone destruction

planned. Any symptom of recurrence were not observed during 2-year follow-up.

Case 3

49-year-old female patient referred to our clinic in June 2015 with the complaint of a slow growing asymptomatic lesion localized in mid palate of the premolar region. Clinically the surface of the lesions was not ulcerated. The adjacent teeth

were vital and asymptomatic. Radiological examination with ortopantomograph and CBCT did not show any sign of destruction (Figure 3A-3B). The aspiration biopsy was applied and it was negative. A wedge-shaped incisional biopsy of the lesion was performed, where the lesion was pronounced. Histopathological evaluation showed low-grade MEC. Patient referred to otorhinolaryngology department for further diagnosis and treatment. The local excision was performed with no additional treatment. Patients were followed for 2 years until now and still been kept under close follow up.

DISCUSSION

There are many causes for soft tissue swellings localized in the palatal region. These swellings might be considered as simple infections established during a general dental examination. However these lesions may be an asymptomatic unrecognized neoplasm. It is important to keep in mind that the lesion might be a neoplasm in the presence of suspicious lesions for diagnosing and treatment planning.Occasionally it is clinically difficult to distinguish a palatal expansion from a neoplasm. Asymptomatic lesions that located in the palatal region generally considered as Pleomorphic adenoma since it is the most frequent salivary gland tumor.9 Histopathological evaluation is vital in these situations not to leave out any doubt. Epithelial minor salivary gland tumors comprise %5 of all head and neck malignancies.5 Minor salivary gland tumors consist %10-15 of all salivary gland tumors and they are generally malignant.5

Two retrospective studies showed that malignancy of minor salivary glands are approximately %44 and the most seen malignant salivary gland tumor is reported as MEC with the ratio of %48-52.10, 11 In a retrospective study conducted in Iran between March 2000 to 2015, it is reported that pleomorphic adenoma is the most common lesion, followed by mucoepidermoid carcinoma and adenocyctic carcinoma with the frequency of %32.6, %27,1 and %22.2 respectively.12

MEC is generally associated with parotid gland and then with the submandibular gland. If the lesion is related with minor salivary gland, it is usually located in the palatal region.8,13,14 Ord et al.14, reported that 15 of 18 smooth surfaced MEC lesions were located in the junction of soft and hard palate and 3 of the lesions were on the hard palate and these 3 lesions were derived from minor salivary gland as consistent

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with the literature. In this case report one of the lesions was seen in hard palate and the others were localized in the soft and hard palate.MEC is often seen in females compared to males12, 15, 16. Although it is usually seen in 5th decade, it may also occur in 4th and 6th decades.16 The cases presented are consistent with the literature as all the patients are female at 4th and 5th decade.Necrotizing sialometaplasia, metastating squamous cell carcinoma and adenosquamous carcinoma should be thought as the differential diagnosis.17 Painless, slow growing, bluish purple colored swellings should bring MEC to mind.18

Histopathologically MEC is classified as low-intermediate- high grade lesions according to cytological atypia and the numbers of mucous, epidermoid and intermediate cells in the specimen.19 Low grade tumors contain more mucous cells and have better prognosis than high-grade tumors.20-22 Low grade tumors are most common type of MEC followed by high grade then intermediate grade lesions with the ratio of %48, %38.7 and %13.3 respectively.16 In this case report, histopathological evaluation showed all the lesions were low-grade tumors and the prognosis is hopeful. High grade tumors are painless, fast growing lesions that may cause extraoral ulcerations, infiltrate to adjacent tissues and metastases while low grade tumors are generally slow growing, asymptomatic lesions that are smaller than 5 cm diameter.19 High grade tumors generally metastases to lymph nodes, lungs and bones. 5 In some cases the lesion may be bluish purple colored like a vascular lesion. This kind of clinical appearance is associated with mucin accumulation.8 All presented cases are slow growing bluish-purple colored lesions.Radiographically Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) images evaluated for the salivary gland tumors.13 In the literature it is reported that CT and MRI results does not differ from each other. On the other hand there are some papers claiming that MRI is superior to CT images because it is more convenient for determining whether the lesion is malignant or not.23 In the presence of destruction of the adjacent bone the lesion’s borders may seem uneven. Root resorption and the mobility of the adjacent teeth may be a sign of the lesion infiltrating to the alveolar bone.6 All 3 cases presented have been examined with a CBCT to see if there was a bone destruction thus minor resorption of the palatal bone. It may be helpful to have MRI besides the CT images when

the signs of a malignant lesion are present such as uneven destruction of the bone. In the literature there are some different treatment approaches for MEC. Local excision of the lesion with solid margins is generally preferred treatment method, considering that %75 of Mucoepidermoid tumors are low- grade and rarely metastasis.14,20 Partial maxillectomy or palatal fenestrations are recommended for the treatment of lesions that are bigger and infiltrated to the bone, while for the lesions that are clinically and radiographically asymptomatic, it is recommended to treat with only soft tissue excision.14,20 Eversole et al.24 treated 17-low and intermediate grade minor salivary gland tumor cases with excision and wide local excision. When bony erosion was present resection was performed and the success rate was reported as %100.24 It is also recommended by Melrose et al that the adjacent bone can be protected when the bone is not affected.25 While some authors recommend this conservative approach, some authors advocate more aggressive treatment modalities. Olsen et al.26 studied on 54 patients with intraoral mucoepidermoid lesions along 25 years and suggested that all lesions should be resected with a partial maxillectomy without investigating the degree of the lesions. Robert et al excised 18 palatal mucoepidermoid lesions during 15 years’ time with 1 cm solid borders due to the lesions slow growing and generally non-infiltrating character. Two of the patients had resection because the bony invasion was present. After the surgical removal of the lesions, the invasion through periosteum and the bone was not visible. So these structures were protected by a palatal apparatus to support the secondary healing.14

Survival rate of the low grade tumors is %95, intermediate and high grade tumors’ survival rate decreases to %50.27 These ratios are important for understanding the significance of histopathological subtype affecting the treatment modality and prognosis. All 3 cases presented in this case report were evaluated as low-grade mucoepidermoid carcinoma, 2 of the cases were treated with only soft tissue excision and neither of them get chemotherapy or radiotherapy. The third patient was treated with hemimaxillectomy and radiotherapy because of the invasion to the bone. Recurrence is not seen at none of the patients after two-year follow up supporting the literature that the low- grade lesions had better prognosis.Postoperative radiotherapy is indicated for the lesions that are resected with solid margins.8 Radiotherapy is also

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recommended for lesions that have lymph node metastasis, bone or perineural invasion, lymphovascular involvement, recurrence and anaplasia.28 Hosokawa et al.29 reported that after applying 55Gy radiotherapy, they manage to control the lesion locally and had survival. One of the cases in this report had 65Gy radiotherapy after hemimaxillectomy.Mucoepidermoid carcinoma is the second most seen salivary gland tumor after pleomorphic adenoma. It is important to keep MEC in mind as a definitive diagnosis for the asymptomatic, slow growing lesions localized in the palatal region with smooth surface. Histopathological examination following a detailed clinical and radiological examination, that leaving no doubts, is crucial for planning a decent treatment modality for patients’ health and prognosis.

REFERENCES

1. Gassler N, Erbe M, Caselitz J, Donner A. Mucoepidermoid carcinoma of palatinal glands with exuberant foreign-body giant cell reaction. Pathol Res Pract 2008; 204: 689-691.

2. Pires FR, Chen SY, da Cruz Perez DE, de Almeida OP, Kowalski LP. Cytokeratin expression in central mucoepidermoid carcinoma and glandular odontogenic cyst. Oral Oncol 2004; 40: 545-551.

3. Bell D, El-Naggar AK. Molecular heterogeneity in mucoepidermoid carcinoma: conceptual and practical implications. Head Neck Pathol 2013; 7: 23-27.

4. El-Naggar AK, Lovell M, Killary AM, Clayman GL, Batsakis JG. A mucoepidermoid carcinoma of minor salivary gland with t(11;19)(q21;p13.1) as the only karyotypic abnormality. Cancer Genet Cytogenet 1996; 87: 29-33.

5. Devaraju R, Gantala R, Aitha H, Gotoor SG. Mucoepidermoid carcinoma. BMJ Case Rep 2014; 2014: bcr-2013-202776.

6. Ritwik P, Cordell KG, Brannon RB. Minor salivary gland mucoepidermoid carcinoma in children and adolescents: a case series and review of the literature. J Med Case Rep 2012; 6: 182.

7. Flaitz CM. Mucoepidermoid carcinoma of the palate in a child. Pediatr Dent. 2000; 22:292-293.

8. Werther PL, Alawi F, Lindemeyer RG. Mucoepidermoid carcinoma of the palate in adolescence. J Dent Child (Chic) 2015; 82: 57-61.

9. Yolcu UAH, Cakır E. Pleomorphic Adenoma: 3 cases report. J Dent Fac Ataturk Uni 2016; 14: 27-31.

10. Pires FR, Pringle GA, de Almeida OP, Chen SY. Intra-oral minor salivary gland tumors: a clinicopathological study of 546 cases. Oral Oncol 2007; 43: 463-470.

11. Yih WY, Kratochvil FJ, Stewart JC. Intraoral minor salivary gland neoplasms: review of 213 cases. J Oral Maxillofac Surg 2005; 63: 805-810.

12. Taghavi N, Sargolzaei S, Mashhadiabbas F, Akbarzadeh A, Kardouni P. Salivary Gland Tumors: A 15- year Report from Iran. Turk Patoloji Derg 2016; 32: 35-39.

13. Sudhakar S, Velugubantla RG, Erva S, Chennoju SK. Management of Mucoepidermoid Carcinoma of the Palate Utilizing (18)F-FDG PET/CT. J Clin Imaging Sci 2014; 4: 5.

14. Ord RA, Salama AR. Is it necessary to resect bone for low-grade mucoepidermoid carcinoma of the palate? Br J Oral Maxillofac Surg 2012; 50: 712-714.

15. Neville WB DD, Allen CM, et al. Oral And Maxillofacial Pathology. 2002; 2:420.

16. Qureshi SM, Janjua, O.S., Janjua, S.M. Mucoepidermoid carcinoma: a clinico-pathological review of 75 cases. Int J Oral Maxillofac Pathol 2012: 5-9.

17. Brandwein MS, Ivanov K, Wallace DI, Hille JJ, Wang B, Fahmy A, et al. Mucoepidermoid carcinoma: a clinicopathologic study of 80 patients with special reference to histological grading. Am J Surg Pathol 2001; 25: 835-845.

18. Baumgardt C, Gunther L, Sari-Rieger A, Rustemeyer J. Mucoepidermoid carcinoma of the palate in a 5-year-old girl: case report and literature review. Oral Maxillofac Surg 2014; 18: 465-469.

19. Rajendran R. Tumors of the salivary glands, Shafer’s Text book of Oral Pathology 2009; 6: 232.

20. Kumar AN, Nair PP, Thomas S, Raman PS, Bhambal A. Mucoepidermoid carcinoma of sublingual gland: a malignant neoplasm in an uncommon region. BMJ Case Rep 2011; 2011.

21. Fox PC, Ship, J.A. . Salivary gland diseases, Burket’s oral medicine 2008; 11: 219.

22. Mathew AL, Joseph BB, Sarojini DM, Premkumar P, Nair SS. Mucoepidermoid carcinoma of palate - a rare entity. Clin Pract 2017; 7: 1009.

23. Yabuuchi H, Fukuya T, Tajima T, Hachitanda Y, Tomita K, Koga M. Salivary gland tumors: diagnostic value of gadolinium-enhanced dynamic MR imaging with histopathologic correlation. Radiology 2003; 226: 345-354.

24. Eversole LR, Rovin S, Sabes WR. Mucoepidermoid carcinoma of minor salivary glands: report of 17 cases with follow-up. J Oral Surg 1972; 30: 107-112.

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25. Melrose RJ, Abrams AM, Howell FV. Mucoepidermoid tumors of the intraoral minor salivary glands: a clinicopathologic study of 54 cases. J Oral Pathol 1973; 2: 314-325.

26. Olsen KD, Devine KD, Weiland LH. Mucoepidermoid carcinoma of the oral cavity. Otolaryngol Head Neck Surg 1981; 89: 783-791.

27. Jarvis SJ, Giangrande V, Brennan PA. Mucoepidermoid carcinoma of the tonsil: a very rare presentation. Acta Otorhinolaryngol Ital 2013; 33: 286-288.

28. Bai S, Clubwala R, Adler E, Sarta C, Schiff B, Smith RV, et al. Salivary mucoepidermoid carcinoma: a multi-institutional review of 76 patients. Head Neck Pathol 2013; 7: 105-112.

29. Hosokawa Y, Shirato H, Kagei K, Hashimoto S, Nishioka T, Tei K, et al. Role of radiotherapy for mucoepidermoid carcinoma of salivary gland. Oral Oncol 1999; 35: 105-111.