Expression and clinical significance of TrkB in sinonasal squamous cell carcinoma: a pilot study

Previous studies have confirmed that tropomyosin-related kinase B (TrkB) plays a critical role in the occurrence, development, and metastasis of many kinds of malignant tumour. More recently, TrkB was found to be overexpressed in head and neck squamous cell carcinoma (SCC) and to be involved in multistep tumour progression. In this study, the expression of TrkB was investigated in 27 cases of sinonasal SCC using an immunohistochemical method. The clinical significance and possible role of TrkB as a prognostic marker in these tumours was also explored. The results showed that TrkB was overexpressed in all cases of sinonasal SCC. A high level of expression of TrkB was significantly related with poor-to-moderate differentiation of SCC (P=0.026), high clinical stage (P=0.023), and the presence of local recurrence (P=0.004). Analysis by Kaplan-Meier method indicated that patients with high levels of TrkB expression had shorter overall survival (P=0.006) and disease-free survival (P=0.018). Multivariate analysis revealed that the level of TrkB expression was an independent prognostic factor for both overall and disease-free survival (P=0.019 and P=0.048, respectively). These data suggest that the overexpression of TrkB may play a significant role in sinonasal SCC and that TrkB may be used as a potential prognostic marker for the clinical outcome.