Abstract
Myoepithelioma is an extremely rare tumor of the salivary glands and it accounts for less than 1% of all salivary gland tumors. In our department, we experienced 315 cases of salivary gland tumors over the past 10 years, but myoepitheliomas were only found in 2 cases. These two cases of myoepithelioma arising from the parotid gland are reported. Case 1 was a 57-year-old male who presented with a painless mass in the left parotid region. A surgical resection was performed and no adhesions of the tumor with the masseter and facial nerve were seen. Histopathologically, the tumor was composed of spindle-shaped cells and hyalinized stroma, and some tumor cells which ultrastructurally contained myofilaments. Another case was a 53-year-old female who was treated in the same manner as case 1. Sixty-eight cases of myoepithelioma of the salivary glands have been reported over the last 10 years in Japan. On the other hand, only 10 cases with a parotid origin have been reported. Histologically, myoepithelioma are classified into four types, and our two observed cases were both spindle cell type.
