Serum IL10 and circulating CD4⁺CD25high regulatory T cell numbers as predictors of clinical outcome and survival in patients with head and neck squamous cell carcinoma

BACKGROUND: Patients with head and neck squamous cell carcinoma (HNSCC) commonly have an imbalance in T helper (Th)1/Th2-type cytokines and elevated levels of CD4(+) CD25(high) regulatory T cells (Treg). Here, we investigated the association of circulating interleukin (IL)10, IL12, and Treg-cells with clinical outcome in patients with HNSCC. METHODS: Serum cytokine levels were determined by enzyme-linked immunosorbent assay (ELISA) in patients' pretreatment (n = 107) and 4 to 6 weeks posttreatment (n = 43), and in nontumor controls (n = 40). Treg-cell levels were determined by flow cytometry. RESULTS: IL10 detectability was significantly higher in patients than controls (p = .001). Pretreatment IL10 levels in all anatomical subsites, except the oral cavity, were significantly elevated in stages III/IV, N+ patients, and in T3/4-tumors (p = .005, .037, and .001, respectively). The detectability of IL10 significantly correlated with poorer survival after a maximum follow-up of 36 months. Treg-cell levels did not correlate with any clinical parameters. CONCLUSION: IL10 is a potential independent factor in predicting a poor clinical outcome in newly presenting tumors of laryngeal and pharyngeal origin. The role of circulating Treg-cells as predictors of clinical outcome requires further investigation.