Natural killer cell activity for IFN-gamma production as a supportive diagnostic marker for gastric cancer

Background/Aim: Decreased Natural killer cell activity (NKA) for interferon-gamma production (NKA-IFN gamma) has been reported in cancer patients. The aim of this study was to determine the diagnostic performance of NKA-IFN gamma for gastric cancer (GC). Results: NKA-IFN gamma levels were decreased in 261 GC patients with all stages of tumor compared to those in 48 healthy donors (P < 0.001), and lower levels of NKA-IFN gamma were associated with higher GC stages. NKA-IFN gamma levels were also associated with clinicopathological parameters including tumor size, depth of invasion, and lymph node metastasis. NKA-INF gamma assay had better diagnostic value (AUC = 0.822) compared to serum CEA (0.624) or CA19-9 assay (0.566) (P < 0.001). Using different cut-off levels, serum CEA and CA19-9 showed sensitivities of 6.1-14.2% and 4.2-28.0%, respectively, which were much lower than that of NKA-IFN gamma (55.6-66.7%). Methods: This study included 261 patients with newly diagnosed GC and 48 healthy donors. NKA for IFN gamma was determined by enzyme immunoassay after incubation of whole blood, and diagnostic performance was evaluated. Conclusions: NK cell activities for IFN gamma production could be used as a supportive non-invasive tumor marker for GC diagnosis.