T-helper Type 1 and 2 Cytokine Levels in Patients with Benign and Malignant Salivary Gland Tumors

Background: Salivary gland tumors are among malignancies that have high recurrence rate. Immune responses in salivary gland tumors have not been well elucidated. T helper type 1 (Th1) and Th2 cytokines have been reported to play a role in the outcome of head and neck cancers. Objective: To evaluate the serum levels of interferon gamma (IFN-gamma), as the hallmark of Th1 cytokines, and interleukin-4 (IL-4), as the hallmark of Th2 cytokines, in patients with benign and malignant salivary gland tumors in comparison with healthy controls. Methods: Fifty patients with benign and 14 patients with malignant salivary gland tumors, as well as 23 healthy individuals were recruited. Serum levels of IFN-gamma and IL-4 were measured using ELISA method. Nonparametric tests were used for data analysis. Results: Serum levels of IFN-gamma and IL-4 were found not to be significantly different in patients compared to the control group (0.68 +/- 0.29 vs. 1.03 +/- 0.57 pg/ml, p=0.58 for IFN-gamma, 4.57 +/- 1.57 vs. 4.41 +/- 1.31 pg/ml, p=0.28 for IL-4). IFN-gamma and IL-4 serum levels were also not significantly different between patients with benign and malignant salivary gland tumors (p=0.54 and p=0.86, respectively). Conclusion: The systemic levels of IL-4 and IFN-gamma seem not to be associated with salivary gland tumor in our study. Investigation of other cytokines produced by Th1 and Th2 cells are warranted.