Immunohistochemistry of local immunoglobulin production in nasopharyngeal carcinoma.

Immunohistochemical investigations by the immunoperoxidase method have been carried out on sections of biopsy specimens obtained from the primary tumour sites of patients with nasopharyngeal carcinoma (NPC). It was found that, in many of the sections thus examined, there was an accumulation of plasma cells, particularly of the IgA type, in the connective tissues surrounding nests of NPC cells. Similar accumulation of plasma cells in the subepithelial connective tissues was likewise observed in a case of choanal polyp. Plasma cells were rarely observed in the section of a biopsy specimen of non-neoplastic oropharyngeal mucosa. These results indicated that the nasopharynx may be a site for the local production of IgA, but the antigenic specificity of these molecules is, however, not known. The possibility that the nasopharynx is a site for the local production of antibodies to the Epstein-Barr virus (EBV)-related antigens was discussed.