The effect of epithelial and myoepithelial differentiations on survival in a parotid gland undifferentiated carcinoma: case report and review of the literature.
Undifferentiated carcinoma of the parotid gland is a rare tumor, with an incidence of 5-10% among all parotid tumors. Salivary gland tumors frequently present myoepithelial cell differentiation. Recognition of myoepithelial cell differentiation is not easily apparent on routinely stained sections and it often requires immunohistochemical or ultrastructural studies. The relationship between these differentiations and survival is still not clear. We report on a 71-year-old male with left parotid undifferentiated small cell carcinoma with epithelial and myoepithelial differentiation that relapsed at the parotid region and neck nodes 4 years after he had undergone superficial parotidectomy. The relapsing disease was treated with total parotidectomy and radical left neck dissection. Also, postoperative radiotherapy was given to the left parotid region and the neck. In total, he is alive 8.5 years from the beginning of the disease, and 54 months after the second surgery and radiotherapy. No disease recurrence has occurred ever since. Undifferentiated carcinomas with epithelial and myoepithelial differentiation are rarely seen and differential diagnosis should be made with salivary gland myoepitheliomas and epithelial-myoepithelial carcinomas. Better understanding of the impact of these differentiations on survival will come with the evaluation of more cases of this unusual malignancy.
Aksu
G
G
Italian Hospital, Radiotherapy Department, Istanbul, Turkey.
Karadeniz
A
A
Fayda
M
M
Dizdaroglu
F
F