High expression of interleukin 10 might predict poor prognosis in early stage oral squamous cell carcinoma patients

Background: Interleukin 10 (IL10) plays an important role in immunosuppression and suppression of antitumor immunity. This study examined the IL10 expression of tumor cells and assessed its significance in patients with oral squamous cell carcinoma (OSCC). Methods: Tumor tissues and adjacent normal tissues were obtained from 325 patients with OSCC and were arranged in a tissue microarray. We examined 325 surgical specimens for associations between IL10 expression in tumor cells and clinical parameters of oral cancer. Results: High IL10 expression in OSCC patients was significantly associated with male gender (P <0.001), smoking (P = 0.015), alcohol consumption (P = 0.018), betel quid chewing (P = 0.003), poor relapse free survival (P = 0.012), and poor overall survival (P = 0.001). Patients with high IL10 expression, and particularly early stage OSCC patients, had significantly worse overall survival as defined by the log-rank test (P = 0.014 for all cases; P = 0.004 for early stage patients). In early stage patients, high IL10 expression in tumor cells was associated with poor prognosis (P = 0.018) and a 1.99-fold higher death risk, as determined by Cox regression. Conclusion: High IL10 expression is significantly associated with aggressive clinical manifestations and might be an independent survival predictor, particularly in early stage OSCC patients.