[Immunohistochemical study on differential diagnosis between NPC and malignant lymphoma].

Nasopharyngeal carcinoma (NPC) and malignant lymphoma are common malignant tumors which frequently involve nasopharynx and cervical lymph nodes. Sometimes, it is difficult to distinguish poorly-differentiated NPC, especially undifferentiated NPC, from malignant lymphoma. Paraffin sections of 221 cases of poorly differentiated or undifferentiated NPC and malignant lymphomas were analysed by immunohistochemical techniques (IGSS, ABC, double stain, etc.), The immunohistochemical criteria of differential diagnosis between NPC and malignant lymphomas were proposed and with these criteria, 40 cases which were difficult to distinguish between NPC and malignant lymphoma were identified. In comparison with the methods of SPA, PAP, ABC, IGSS, etc., and the probes of Ke, EMA, LCA, Vi, etc. on paraffin sections, IGSS or ABC method and probes of Ke and LCA were considered to be more sensitive.