Investigation of interleukin 10, 12 and 18 levels in patients with head and neck cancer.

Head and neck squamous cell carcinoma (HNSCC) is an aggressive epithelial malignancy. It is the most common neoplasm arising in the upper aerodigestive tract. Interleukin (IL) 12 and IL-18 are cytokines which have a major anti-tumour activity via stimulation of a T-helper type 1 (Th1) immune response. Interleukin 10, a potent antagonist of IL-12, is a cytokine which possesses immunosuppressive activity mainly produced via T-helper type 2 (Th2) cells. Studies of other types of cancer have shown that the level of IL-12 in serum or tissues is suppressed and/or the IL-10 level is increased, suggesting that there is an impaired cell-mediated anti-tumour response. The aim of this study was to measure pre-operative serum cytokine concentrations in HNSCC patients in order to detect any changes in IL-10, IL-12 and IL-18, compared with non-tumour controls. The relationship between cytokine levels and standard clinicopathological features, including tumour site, tumour stage and presence of nodal metastasis, was also examined. Fifty-seven patients with primary HNSCC were prospectively recruited, together with 40 non-tumour control patients with a similar age and sex distribution. Serum cytokine levels were measured using commercial quantitative enzyme-linked immunosorbent assay. The HNSCC patients had significantly lower IL-12 levels (median; interquartile range) than controls (42.8 pg/ml, 26.2-61.6 vs 52.3 pg/ml, 37.5-113.7; p=0.018). Also, patients were more likely to have detectable IL-10 levels than were controls, as IL-10 was positive in 27/55 patients but in only 9/39 controls (p=0.011). Furthermore, IL-10 detectability varied according to primary site, being more commonly observed in hypopharyngeal and laryngeal tumours, and IL-10 was more likely to be detected with advanced tumour stage (T3 and T4). No differences in IL-18 levels were observed between patients and controls (p=0.169). These results suggest (in agreement with studies on other solid malignancies) that HNSCC causes a significant change in the serum levels of specific Th1 and Th2 cytokines, producing an in vivo environment that is unlikely to promote an effective cell-mediated anti-tumour response.