耳下腺内リンパ上皮性嚢胞の一症例

抄録

A 57 year-old Japanese male was seen with the chief complaints of left parotid gland swelling, pain, trismus.
At the initial visit, a subcutaneous mass, measuring 50 x 70mm, was seen in the left parotid region. The mass was moderately tender and the consistency was soft anteriorly and elastic firm posteriorly. The mobility was restricted with no change in the skin covering the mass. The saliva from the left parotid gland was normal in colour and contents. Various imaging modalities were done preoperatively including CT, MRI, ultrasonography and aspiration biopsy under the ultrasono-graphic guide. None was thus conclusive for the differential diagnosis and our tentative diagnosis was a cystic lesion in the parotid gland.
A partial parotidectomy was performed under general anesthesia and the cystic lesion, measuring 20mm in diameter, was found in the deep lobe. The cyst showed no connection to the external ear canal, and tracts and fistulae were absent.
Histopathological report lead to the definite diagnosis of lymphoepithelial cyst. A mild and incomplete facial palsy on the left had been noted for more than 10 years and this, however, improved after the surgery.