Acta Med. Nagasaki 38:189- 192 T-cell Rich B-cell Cross-reacting Nasopharyngeal Carcinoma

Immunohistochemical analysis was carried out to examine infiltration of lymphocytes in the tumor nests of nasopharyngeal carcinoma (NPC) using 38 biopsy cases obtained from southern China. These cases were divided into 3 groups according to their prominent pattern associated with the cell and the tissue differentiation using the World Health Organaization (WHO) classification as follows: (i) 6 cases of squamous cell carcinoma (16%), (ii) 25 cases of differentiated non-keratinizing carcinoma (66%), (ii) 7 cases of undifferentiated carcinoma (18%). All tumor tissues reacted diffusely with MB-1, however, these did not react with L26 (CD20), 4KB5 (CD45R), MT-1, and leukocyte common antigen (LCA). In the tumor nests, normal lymphocytes were observed in squamous cell carcinoma type (50%), differentiated non-keratinizing carcinoma type (72%), and undifferentiated carcinoma type (86%). Therefore, it is suggested that a large number of infiltrating non-neoplastic T-cells may be related to good prognosis. T-cell-rich B-cell lymphomas (TCRBCLs) are recently described as unusual non-Hodgkin's lymphomas associated with predominance of reactive T-cells. Therefore, the mechanism of T-cell lymphocyte infiltration adjacent o the tumor cell is considered that these T-cell infiltrates may be the passive response to cytokine secretion by the tumor cells