It has been reported that mucosa-associated lymphoid tissue (MALT) lymphoma is an extranodal low-grade lymphoma arising in the stomach, lung, salivary gland and thyroid, and is characterized by centrocyte-like cell and lymphoepithelial lesion. We experienced a case of MALT lymphoma arising in the parotid gland.
A 30-year-old woman visited the hospital because of a left preauricular mass. A 2.0×1.0cm tumor was palpated in the anterior region of the left ear. Ultrasonography revealed a well-defined and low echoic tumor. Aspiration cytology revealed glandular epithelium. The tumor was extipated under a diagnosis of parotid tumor. Histological finding showed the diffuse invasion of medium-sized lymphoma cells accompanying by lymphoepithelial lesions in the parotid gland. From these findings, it was diagnosed MALT lymphoma arising in parotid gland. Postoperatively, three courses of CHOP therapy was conducted and the patient has been free from the disease, as of 10 months after the operation.