Parotid Gland Myoepithelioma: A Rare Benign Salivary Gland Tumour with Rapid Clinical Progression
摘要
Myoepitheliomas are rare benign salivary gland tumours, representing less than 1% of all salivary gland neoplasms. They most commonly arise in the parotid gland and can pose diagnostic challenges due to clinical, radiological, and histopathological overlap with pleomorphic adenoma and other benign or malignant salivary gland tumours, particularly when atypical features such as rapid growth are present.
Case ReportA 63-year-old male presented with a rapidly progressive, painless swelling in the right parotid region. Imaging revealed a well-defined solid–cystic lesion in the superficial lobe of the parotid gland. The unusually rapid clinical progression raised suspicion of malignant salivary gland tumours in addition to benign entities such as pleomorphic adenoma or Warthin’s tumour. Superficial parotidectomy(ESGS Parotidectomy I-II) was performed. Intraoperatively, the lesion appeared well-encapsulated with clear planes of dissection and without evidence of local tissue infiltration, favouring a benign pathology. Histopathological examination demonstrated an encapsulated myoepithelioma composed of spindle and epithelioid cells within a hyaline stroma. Surgical margins were free of tumour.
ConclusionMyoepithelioma of the parotid gland is an uncommon entity. Accurate diagnosis relies primarily on histopathological evaluation, as radiological features often mimic other salivary gland tumours. Atypical clinical behaviour may further complicate diagnosis and influence surgical decision-making. Complete surgical excision offers an excellent prognosis.