Malignant lymphoma in the head and neck associated with benign lymphoepithelial lesion of the parotid gland

Lymphoepithelial lesion is a benign lymphoproliferative disease occasionally arises in the salivary glands, but association with malignant diseases or autoimmune diseases has also been discussed. We herein present three cases of malignant lymphoma arose in the parotid gland and the lacrimal gland, following parotid surgery for benign lymphoepithelial lesion (BLEL) of the parotid gland. Two cases had mucosa associated lymphoid tissue (MALT) lymphoma in the parotid gland; one arose in the ipsilateral parotid gland as a recurrent swelling, and the other arose in the contralateral parotid gland of the previous BLEL surgery. The third case of malignant lymphoma arose in the lacrimal gland on the ipsilateral side, and the following contralateral parotid gland remained BLEL. All three patients were female, and one patient had a past history of Sjögren's syndrome and Hashimoto's disease. All three patients were treated by chemotherapy and one patient received additional radiotherapy. To follow-up lymphoproliferative diseases in the salivary glands such as BLEL, careful observation should be made on the same gland, other major salivary glands, and other organs in the head and neck, especially in females with autoimmune diseases.