Epithelial-myoepithelial carcinoma originating from a minor salivary gland in the nasal septum: A case report and literature review

Abstract

Rationale: Epithelial-myoepithelial carcinoma is an extremely rare, malignant neoplasm that occurs most frequently in the major salivary glands and accounts for approximately 1% of all salivary gland neoplasms. Few reports have described the presence of epithelial-myoepithelial carcinoma in the sinonasal region; hence, the treatment guideline and prognosis remain unclear.

Patient concerns: We reported a case of a 75-year-old woman with complaint of nasal obstruction and frequent epistaxis for 3 years. During the nasal endoscopic examination, a mass in the left nasal cavity originating from the left nasal septum that caused bleeding on touch was observed.

Diagnoses: A diagnosis of epithelial-myoepithelial carcinoma was made based on the features of histopathology and immunohistochemistry of the surgical specimens. The patient was treated by surgical removal of the septal mass using the endonasal endoscopic approach.

Outcomes: In the serial follow-up paranasal sinus imaging and endoscopic inspection, evidence of recurrence was absent for 18 months after surgery.

Lessons: This report highlights a case of epithelial-myoepithelial carcinoma originating from a minor salivary gland in the nasal septum, one of the most unusual locations. Diagnosis of epithelial-myoepithelial carcinoma should be made based on the findings of immunohistochemistry of the operative specimen. Clinicians should consider complete surgical resection as the effective treatment of choice.

Figure 1

Preoperative imaging. (A) Nasoendoscopy reveals a polypoid mass (asterisk) causing bleeding on touch in the left nasal cavity. (B) Axial and (C) coronal contrast-enhanced computed tomography of the paranasal sinuses shows a 3.7-cm enhancing and expanding lesion in the left nasal cavity with accompanied remodeling of the nasal septum and inferior turbinate. IT = inferior turbinate, S = septum.

Figure 2

Intraoperative view. (A) Intraoperatively, the floor and lateral wall of the nasal cavity are intact. Remodeling of the inferior turbinate by the tumor is observed throughout the inferior meatus, but tumor invasion is not evident. (B) The tumor originated from the nasal septum is observed, and removal of the affected septal mucosa along with the tumor is performed. IT = inferior turbinate, S = septum.

Figure 3

Histopathologic features of the tumor. (A) The tumor cells are composed of variable sized ductal structures lined with inner polymorphic epithelial cells surrounded by outer myoepithelial cells (hematoxylin and eosin staining, × 200). In immunohistochemical analysis, (B) the neoplastic myoepithelial cells (ductal cells of the outer layer) show reactivity to p63 (× 200), and (C) the luminal epithelial cells (inner layer) show strong positive immunoreactivity to cytokeratin-7 (× 200); hence, epithelial-myoepithelial carcinoma is diagnosed.

Figure 4

Follow-up paranasal sinus imaging and nasoendoscopic view at 18 months after surgery. (A) Axial and (B) coronal magnetic resonance imaging of the paranasal sinuses show a clear nasal cavity without recurrence. (C) Nasoendoscopy reveals complete resolution of the tumor and recovery of the septal mucosa. IT = inferior turbinate, S = septum.