Local immune reaction in nasopharyngeal carcinoma, with special reference to its prognostic evaluation

A study of the tumor-host interaction was conducted in 30 patients with nasopharyngeal carcinoma (NPC). The local immune reaction was investigated by an immunoperoxidase technique using monoclonal antibodies. Eighteen patients who were clinically suspected to have NPC, but finally proved otherwise, served as controls. There was a significant difference between the number of NPC patients with interleukin-2 receptor (IL-2R)-positive cells (activated T lymphocytes) in the stroma compared with the control. IL-2R positive cells were found in 67% of NPC patients but in only 22% of controls (P less than 0.01). There was a greater infiltration of T lymphocytes in patients with a good outcome compared with patients with a poor outcome. This trend was observed in both the parenchyma (60.2 versus 29.4 x 10(4) cells/mm2) and the stroma (74.7 versus 44.8 x 10(4) cells/mm2). The levels of Leu-3 positive cells (helper/inducer) in the NPC parenchyma were inversely correlated to the extent of the primary tumor, but there was no correlation in the stroma. These findings demonstrate that a local host-immune reaction does exist and may be a useful prognostic indicator for NPC patients.