Investigation of IL-33 serum levels in patients with benign and malignant salivary gland tumors.

BACKGROUND

Interleukin-33 (IL-33) has been recently discovered as an influential factor in the process of tumor immunity, and is presented in cancer pathogenesis.

OBJECTIVE

This study aimed to determine the serum levels of IL-33 in patients with benign and malignant Salivary gland tumors (SGTs).

METHODS

This descriptive cross-sectional study was performed on 47 samples of malignant SGTs including 18 mucoepidermoid carcinoma (MEC), 8 adenoid cystic carcinoma (ADCC), 21 malignant mixed tumor (MMT), and 14 benign pleomorphic adenoma (PA). A control group was considered consisting of 28 healthy subjects. The serum level of IL-33 was measured by using sandwich ELISA method. The data were statistically analyzed through Kruskal-Wallis and Mann-Whitney tests.

RESULTS

The median concentration of IL-33 was 6.91 in malignant, 5.14 in benign, and 5.01 in healthy cases, with a statistically significant difference (P= 0.001). The median serum levels of IL-33 increased significantly in ADCC (7.15), MEC (7.03), and MMT (6.91) compared with the control group (5.01) (P< 0.05). The mean rank of MEC was significantly higher than PA (P= 0.01). IL-33 concentration was positively and significantly correlated with the tumor stage (P= 0.02) and tumor size (P= 0.03).

CONCLUSIONS

IL-33 could be suggested as a novel biomarker to distinguish different types of SGTs.