A rare myoepithelioma of the sinonasal cavity: case report

Abstract

Myoepithelioma is a rare benign neoplasm. Pure accounting for less than 1% of all salivary gland tumors. Only three cases of sinonasal myoepithelioma have been reported in the literature. Diagnosis of myoepithelioma through light microscopy is possible and immunohistochemistry is done to facilitate the diagnosis. The lesion is so rare that there are no specific indications/guidelines for its treatment. We report to you a rare case of sinonasal myoepithelioma in a 57 year old Asian female.Myoepitheliomas are rare tumours that account for only about 1% of all salivary gland tumors. Most are benign, but some can be malignant. Only three cases of sinonasal myoepithelioma have been reported in the literature so far. Case historyA 57 year old female presented to the out-patient department (OPD) of a leading multispeciality teaching hospital with a 3 year history of progressively increasing right sided nasal blockage, a change in voice and a bulge over the hard palate. No history of epistaxis was given. On nasal examination, there was a broadening of the nasal bridge and a large pinkish red polypoidal mass was seen in the right nasal cavity. Oral cavity examination showed a smooth bulge over the hard palate mostly confined on the right side (Figure 1). CT scan done showed an oval lobulated iso-dense patchily enhancing mass measuring about 7.0 × 5.0 cm with its epicentre in nasal vault and the ethmoids (Figure 2).An incisional biopsy was performed as an OPD procedure and this revealed loose clusters of plasmacytoid (hyaline) myoepithelial cells (40×).Subsequently, following a multidisciplinary meeting, the patient underwent a sublabial surgical approach for resection of the tumor. On table the sessile, encapsulated, pinkish red and firm tumor was occupying whole of the nasal cavity with the septum pushed to the left side. Histopathological examination of the specimen revealed loose clusters of plasmacytoid (hyaline) small and/or medium sized spindle shaped cells, differently interlaced, with eosinophilic cytoplasm, occurring in sheets or swirls; the nuclei were predominantly round to ovoid in shape, often eccentric, with finely dispersed chromatin and low mitotic activity. Further Immunohistochemical studies revealed positivity to Calponin (Figure 3). These results were consistent with the rare diagnosis of a sinonasal myoepithelioma. Patient had no recurrence during a follow-up period of 2 years.

Myoepithelioma of the parotid gland in a child: a case report

“…Epithelial salivary gland tumors are very rare in children [1]. Myoepitheliomas account for less than 1% of all salivary gland tumors and are usually located in the parotid gland [2][3][4][5][6]. Myoepitheliomas arise from myoepithelial cells, which are present in many secretory organs such as major and minor salivary glands, lacrimal glands, breasts, and sweat glands [2,3].…”

“…Myoepitheliomas account for less than 1% of all salivary gland tumors and are usually located in the parotid gland [2][3][4][5][6]. Myoepitheliomas arise from myoepithelial cells, which are present in many secretory organs such as major and minor salivary glands, lacrimal glands, breasts, and sweat glands [2,3]. Although these tumors occur over a wide age range, they are usually seen between the fourth and fifth decades of life [4,6].…”

“…Only a few cases with myoepithelioma of salivary glands that occurred in the palate have been reported in children up to date [5,7]. Their prevalence is the same in both sexes [2,3,5,6]. These tumors usually occur as a painless and slowly growing mass, but may occasionally be locally aggressive [2][3][4].…”

“…In addition, they are often located in the superficial lobe of the parotid gland and often attached the capsule of the gland [8]. However, these findings are not specific for myoepitheliomas [3,9]. The diagnosis of myoepithelioma should be made mainly on the basis of histopathologic features.…”

Anaplastic Myoepithelial Carcinoma of the Sinonasal Tract: an Underrecognized Salivary-Type Tumor Among the Sinonasal Small Round Blue Cell Malignancies? Report of One Case and a Review of the Literature

“…Only a few primary myoepitheliomas arising in this region have been published as isolated case reports [14][15][16][17]. To the best of our knowledge, only two cases of MECA in the sinonasal region (both located in the maxillary sinus) have previously been published [18,19].…”