|Year : 2020 | Volume
| Issue : 8 | Page : 233-236
Epithelial–myoepithelial carcinoma at the base of the tongue presented with metastatic disease in the absence of myoepithelial anaplasia
Mahima Yadav, Neha Gupta, Richa Katiyar, Shashikant C U. Patne
Department of Pathology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
|Date of Submission||02-Oct-2017|
|Date of Decision||22-Apr-2020|
|Date of Acceptance||12-Aug-2020|
|Date of Web Publication||28-Dec-2020|
Shashikant C U. Patne
Department of Pathology, Homi Bhabha Cancer Hospital, Old Loco Colony, Shivpurwa, Lahartara, Varanasi - 221 002, Uttar Pradesh
Source of Support: None, Conflict of Interest: None
Epithelial–myoepithelial carcinoma (EMC) is a biphasic low-grade malignant tumor that shows ductal structures lined by the ductal cells with surrounding myoepithelial cells. EMC is most commonly reported in the parotid gland followed by other major and minor salivary glands. EMC of the tongue is an extremely uncommon tumor, with only five previously published case reports. We herein report the sixth case of EMC of the tongue. A 40-year-old female who had throat pain, dysphagia, and right earache for 3 years showed a 4 cm × 4 cm nodular tumor at the base of her tongue. Histopathological and immunohistochemical features were diagnostic of EMC with cervical lymph node metastasis. The metastatic behavior of EMC of the tongue in the absence of myoepithelial anaplasia or high-grade histological features is unusual and reported in this case report for the first time.
Keywords: Cytokeratin, cytology, malignancy, oral cavity, salivary gland
|How to cite this article:|
Yadav M, Gupta N, Katiyar R, Patne SC. Epithelial–myoepithelial carcinoma at the base of the tongue presented with metastatic disease in the absence of myoepithelial anaplasia. J Can Res Ther 2020;16, Suppl S1:233-6
|How to cite this URL:|
Yadav M, Gupta N, Katiyar R, Patne SC. Epithelial–myoepithelial carcinoma at the base of the tongue presented with metastatic disease in the absence of myoepithelial anaplasia. J Can Res Ther [serial online] 2020 [cited 2021 Jan 25];16:233-6. Available from: https://www.cancerjournal.net/text.asp?2020/16/8/233/305132
| > Introduction|| |
Epithelial–myoepithelial carcinoma (EMC) is a rare malignant tumor of the salivary gland that predominantly occurs in the elderly age group (mean age 61 years), with a slight female preponderance. The most common site of EMC is the parotid gland (62.1%), followed by the sinonasal mucoserous glands (10.3%), palate (8.6%), and submandibular gland (8.6%). However, EMC involving the tongue is extremely uncommon with only five previously reported cases.,,,, Further, only a single case of EMC of the tongue showed lymph nodal and possibly pulmonary metastases. We herein report the sixth case of EMC of the tongue and the second one presenting with lymph nodal and possibly pulmonary metastases.
| > Case Report|| |
A 40-year-old female presented with complaints of throat pain, difficulty in swallowing, and right earache for the last 3 years. Her intraoral examination revealed a 4 cm × 4 cm submucosal nodular mass over the base of the tongue [Figure 1]a. There was no evidence of ulceration over the mass lesion, restriction of tongue movement, or presence of any other lesion in the oral cavity. A palpable right cervical lymph node measuring 1 cm × 1 cm was present. Contrast-enhanced computed tomography scan of the neck showed a well-defined, homogeneously enhancing, soft tissue density mass lesion arising from the base of the tongue on the right side [Figure 1]b, with infiltration of muscles of the floor of mouth with the involvement of supraglottic larynx. Right level II, V, and VII cervical lymphadenopathy was also evident. A small biopsy taken from the mass over the base of the tongue showed unremarkable stratified squamous epithelial lining and a subepithelial infiltrative tumor arranged in tubules [Figure 2]a, which was formed by distinct luminal and abluminal layers [Figure 2]b. The luminal cells were cuboidal with mildly pleomorphic nuclei, dispersed chromatin, and eosinophilic cytoplasm. The abluminal cells were polygonal with eccentric nuclei and abundant clear cytoplasm. There was no evidence of anaplasia, increased mitosis, lymphovascular invasion, perineural invasion, or necrosis. On immunohistochemistry, the inner ductal cells were CK+/CK7+/EMA+/CD117+/S100 protein+/SMA-/CD10- [Figure 2]c,[Figure 2]d,[Figure 2]e,[Figure 2]f,[Figure 2]g. The outer clear cell layers were SMA+/CK+/S100 protein+/CD117+/CD10-/CK7-/EMA- [Figure 2d, e, and g]. Fine-needle aspiration cytology (FNAC) of the right cervical lymph node showed cellular smears with the presence of the subtle biphasic pattern of tumor cells, with cohesive clusters and vague tubules on a background of the dyscohesive oval nuclei with abundant clear cytoplasm in few cells [Figure 2h]. Significant nuclear atypia, abnormal mitotic activity, or necrosis was not present. Chest X-ray showed evidence of bilateral pulmonary metastases; however, FNAC or biopsy was not done from the lung lesions owing to the patient's refusal. Based on the clinical, radiological, and pathological findings, the patient was diagnosed as EMC of the base of the tongue with right cervical lymph node metastasis and suspected bilateral pulmonary metastases. Since the patient was inoperable due to disseminated disease, she was referred for receiving chemo-radiotherapy for further management.
|Figure 1: (a) Clinical photograph showing intraoral nodular mass involving the base of the right tongue (arrow). (b) Computed tomography scan showing obliteration of lingual sulcus by an infiltrative tumor present in the posterior part of the tongue (asterisk)|
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|Figure 2: (a) Stratified squamous epithelial lining (short arrow) with underlying infiltrative nests of tumor arranged in tubules (long curved arrow) (H and E, ×100). (b) Tumor nests with tubular architecture lined by luminal cuboidal cell layer (short arrow) and abluminal polygonal clear cells (long arrow) (H and E, ×200). (c) Cytokeratin stain highlighting infiltrative tumor nests as well as overlying stratified squamous epithelium (arrows) (Diaminobenzidine, ×40). (d) Strong expression of cytokeratin in the luminal cells (arrow) while weak expression is noted in the abluminal clear cells (Diaminobenzidine, ×400). (e) Smooth muscle actin strongly expressed in outer myoepithelial cell layer (arrow) while inner epithelial cell layer is negative (Diaminobenzidine, ×400). (f) CD117 staining predominantly seen in the inner epithelial cells (Diaminobenzidine, ×400). (g) S-100 protein expressed in both epithelial and myoepithelial cells (Diaminobenzidine, ×100). (h) Cytology smears showing subtle tubular arrangement with background scattered bare nuclei and occasional polygonal clear cells (arrows) (Papanicolaou stain, ×400)|
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| > Discussion|| |
EMC is histologically characterized by well-defined tubules with dual cells: an outer myoepithelial cell layer with clear cytoplasm surrounding an inner lining of eosinophilic cuboidal epithelial cells resembling intercalated ducts. The inner ductal cells are strongly immunoreactive for pan-cytokeratin and variably positive for S-100 protein but are negative for myoepithelial markers. The myoepithelial cells are positive for p63, SMA, calponin, and pan-cytokeratin (often weak)., Bcl-2 and c-kit (CD117) are frequently positive in EMC. We have observed the characteristic biphasic pattern of tumor on histology and cytology, which was also confirmed by immunohistochemistry.
The cytological findings in EMC resemble histological features with biphasic cytomorphology. Cytological smears of EMC are cellular with the presence of subtle tubule formation by epithelial cells, having larger, mildly pleomorphic nuclei and scanty cytoplasm. In contrast, the myoepithelial cells have small, uniform nuclei with abundant clear cytoplasm and distinct cell borders. Because of the fragile cytoplasm of the myoepithelial cells, they usually appear as naked nuclei rather than the intact cells. In the present case, similar FNAC findings were seen in smears from the right cervical lymph node, consistent with cytodiagnosis of metastasis from EMC. To the best of our knowledge, cytological findings of EMC of the tongue have not been reported earlier.
We have reviewed all the previously published cases of EMC of the tongue,,,,, with the inclusion of our case [Table 1]. The mean age of the patients was 54.0 ± 12.5 years. Our patient is the youngest reported case of EMC of the tongue diagnosed at the age of 40 years. The numbers of males and females were equal. Clinical presentations were variable and include dysphagia, weight loss, foreign body sensation in the pharynx, soreness in the throat, altered voice, earache, restriction in tongue movement, and throat pain. The tumor size ranged from 1 cm to 5 cm. Similar to the case report by Chen et al., we have also noticed lymph node metastasis and possibly pulmonary metastases. The other four cases did not report metastasis. Margin-negative surgery with or without chemo-radiotherapy has been successfully used without the evidence of metastasis in four cases.,,, In one of these cases, recurrent tumor after 4 years of primary surgery has been treated with margin-negative repeat surgery, and thereafter, no recurrence or metastasis was reported in a follow-up of 3 years. Histological and immunohistochemical features of EMC of the tongue were similar to EMC involving the major salivary glands. Except for the report by Chen et al., wherein myoepithelial anaplasia and histological high-grade features were present and the patient died in a follow-up of 18 months, no other case showed similar poor outcome. EMC displays aggressive malignant behavior rarely. In such cases, histologically, high-grade nuclear features, brisk mitotic activity, necrosis, myoepithelial anaplasia, and features of dedifferentiation are also noted., These histological features impart rapid tumor progression, metastatic disease, and poor outcome for the patients of EMC. In contrast, our patient had cervical lymph nodal and possibly pulmonary metastases in the absence of these histological features. Thus, findings of our case illustrate metastatic behavior in a long-standing case of EMC of the tongue, even in the absence of myoepithelial anaplasia or aggressive histology.
|Table 1: Comparison of reported cases and present case of epithelial–myoepithelial carcinoma of the tongue|
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| > Conclusion|| |
EMC is a very rare tumor of the tongue which resembles with its counter part in the salivary gland. EMC of the tongue is more often symptomatic and show low rates of recurrence and distant metastasis. In the present case, EMC showed metastasis in the absence of aggressive histological features. The patient had the symptoms related to the lesion for 3 years before she sought medical attention. This is possibly due to low healthcare seeking behaviour in patients coming from rural parts and belonging to low socioeconomic status in India.
More studies are required to better understand its morphology and correlate histological features with clinical course and prognosis; however, this study details the clinicopathological features of EMC of the tongue and should be kept in mind as a possible differential diagnosis of tumors of the tongue.
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.
Authors are grateful to Dr. Arpita and Dr. Ishan Kumar, Department of Radiodiagnosis, Institute of Medical Sciences, Banaras Hindu University, for interpretation of the radiological images of this case.
Financial support and sponsorship
Revolving fund of the Department of Pathology, IMS, BHU, supported the study.
Conflicts of interest
There are no conflicts of interest.
| > References|| |
Seethala RR, Barnes EL, Hunt JL. Epithelial-myoepithelial carcinoma: A review of the clinicopathologic spectrum and immunophenotypic characteristics in 61 tumors of the salivary glands and upper aerodigestive tract. Am J Surg Pathol 2007;31:44-57.
Puri T, Singh K, Sharma DN, Khurana N. Epithelial-myoepithelial carcinoma of the base of tongue: Pathology and management. Indian J Cancer 2004;41:138-40.
] [Full text]
Kumai Y, Ogata N, Yumoto E. Epithelial-myoepithelial carcinoma in the base of the tongue: A case report. Am J Otolaryngol 2006;27:58-60.
Peters P, Repanos C, Earnshaw J, Stark P, Burmeister B, McGuire L, et al
. Epithelial-myoepithelial carcinoma of the tongue base: A case for the case-report and review of the literature. Head Neck Oncol 2010;2:4.
Matos FR, Miranda JL, Mesquita AT, Santos CR, Freitas Rde A. Epithelial-myoepithelial carcinoma in the ventral surface of the tongue. Braz J Otorhinolaryngol 2010;76:540.
Chen MY, Vyas V, Sommerville R. Epithelial-myoepithelial carcinoma of the base of tongue with possible lung metastases. Case Rep Otolaryngol 2017;2017:4973573.
Angiero F, Sozzi D, Seramondi R, Valente MG. Epithelial-myoepithelial carcinoma of the minor salivary glands: Immunohistochemical and morphological features. Anticancer Res 2009;29:4703-9.
Miliauskas JR, Orell SR. Fine-needle aspiration cytological findings in five cases of epithelial-myoepithelial carcinoma of salivary glands. Diagn Cytopathol 2003;28:163-7.
Yang S, Chen X. Epithelial-myoepithelial carcinoma with high grade transformaCon. Int J Oral Maxillofac Surg 2012;41:810-3.
Vüzquez A, Patel TD, D'Aguillo CM, Abdou RY, Farver W, Baredes S, et al
. Epithelial-myoepithelial carcinoma of the salivary glands: An analysis of 246 cases. Otolaryngol Head Neck Surg 2012;41:810-3.
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