Malignant lymphoepithelial lesion of the salivary gland.

Eight cases of malignant lymphoepithelial lesion (MLEL) of major salivary glands, seven of which occurred in Southern Chinese patients, are reported. All but two of the patients were older than 40 years of age; there were five male and three female patients. The parotid and submandibular glands were the sites of origin in equal numbers of cases. Six patients had elevated titers of serum IgA against Epstein-Barr virus capsid antigen. Seven remained well after surgery and local radiation therapy, and one died of miliary tuberculosis without evidence of residual neoplasm. Histologically, MLELs were characterized by syncytial clumps of large cells with vesicular nuclei and prominent nucleoli, admixed with abundant small lymphocytes and plasma cells. Two features not emphasized previously in the literature were the presence of reactive histiocytes in some epithelial islands, producing a starry sky pattern, and perineural invasion, which was identified in four cases. The tumor cells showed strong immunostaining for cytokeratin. The literature concerning this rare tumor is reviewed, and the differential diagnosis between MLEL and benign lymphoepithelial lesion, metastatic undifferentiated carcinoma, and malignant lymphoma is discussed.