The prognostic value of natural killer cell infiltration in resected pulmonary adenocarcinoma

Abstract

Objective: Natural cytotoxicity caused by mediated natural killer cells is believed to play an important role in host-cancer defense mechanisms. Immunohistochemically, we have detected natural killer cells in tissue specimens from patients with pulmonary adenocarcinoma and have assessed their clinical characteristics. Methods: Using the monoclonal antibody for CD57 specific marker for natural killer cells, we quantified natural killer cell infiltration in 150 patients with pulmonary adenocarcinoma who underwent curative tumor resection to investigate the relationship between natural killer cell counts and clinico-pathologic factors and prognosis. Results: The natural killer cell count was significantly related to the regulation of tumor progression, involving T classification, N classification, and stage (P =.01 for T classification or stage; P =.02 for N classification). A significant difference in the rate of patient survival was detected between those patients whose tumors had either high or low natural killer cell counts in both the overall and stage I groups (P =.0002 for the overall group; P=.049 for the stage I group). Conclusion: These data indicate that natural killer infiltration may contribute to the regulation of tumor progression and that the natural killer cell count can serve as a useful prognostic marker in overall and stage I pulmonary adenocarcinoma.