Lymphoid lesions of the oral cavity.

The lymphoid lesions of the oral cavity may be classified into three groups: 1. Benign lesions. 2. Malignant lesions. 3. Other lymphoid-like lesions. 1. Benign lymphoid lesions: In this group the following lesions must be differentiated: reactive lymph node hyperplasia, enlarged follicle of the lingual tonsil, lymphoepithelial cysts, lymphoepithelial lesions, lymphoid polyps, and cystadenolymphomas. The most frequent locations of benign lymphoid lesions are the lingual tonsil, buccal mucosa, tongue, and floor of mouth. 2. Malignant lesions: One subgroup includes the systemic lymphoid diseases, the other subgroup the lymphoid tumors. According to the WHO classification, the following entities belong to systemic lymphoid diseases: acute and chronic lymphoid leukemia, Waldenström's macroglobulinemia, plasma-cell leukemia, heavy-chain disease, Sézary's disease, and chronic lymphoproliferative diseases (unclassified). WHO has classified the lymphoid tumors as follows: lymphosarcoma, mycosis fungoides, plasmacytoma, reticulosarcoma, unclassified malignant lymphomas, Hodgkin's disease. The WHO classification is compared to the Kiel classification. The special cell types and the differences of the two international classifications are interpreted, especially terms such as centroblastic-centrocytic lymphomas, immunoblastic lymphomas, and the different terminology of reticulosarcomas. 3. Other lymphoid-like lesions: The following examples are discussed in relation to the oral cavity: eosinophilic granuloma, sarcoidosis, Melkersson-Rosenthal's syndrome, Wegener's granulomatosis, foreign body granuloma, and other lesions.