Hodgkin's lymphoma of the oropharyngeal region: report of four cases and diagnostic value of monoclonal antibodies in detecting antigens associated with Reed-Sternberg cells.

In a review of more than 500 cases from the Lymphoma Registry, Department of Anatomic Pathology, University Hospital Purpan, Université Paul Sabatier, Toulouse, France, four cases of primary lesions in the oropharyngeal region were found. There were two lesions in the palatine tonsil, one in the nasopharynx, and one in the parotid gland. The average age of the patients was 54.5 years (range, 37 to 70 years), and all patients were men. The histologic types were lymphocyte predominance (one case), nodular-sclerosis (one case), and mixed cellularity (two cases). The patients were respectively staged as IAa, IIAa, and IIIA. They were treated with radiation, chemotherapy, or both. All four patients are now free of tumor and have been followed from 18 months to more than 6 years after definitive diagnosis and appropriate therapy. Immunohistochemistry significantly contributes to the differential diagnosis of atypical Hodgkin's disease from non-Hodgkin's lymphomas, especially in extranodal sites. Dako-EMA and Leu-M1 monoclonal antibodies are reactive, respectively, with L and H variants (Dako-EMA+, Leu-M1-) in the lymphocyte predominance type (Type 1) and with Reed-Sternberg cells (Dako-EMA-, Leu-M1+) in the nodular-sclerosis (Type 2), mixed cellularity (Type 3), and lymphocyte depletion (Type 4) types.