ETS-1 protein is one of the key regulators in tumor invasion and progression. We aimed to evaluate the role of ETS-1 in the invasiveness and progression of laryngeal squamous carcinoma, as well as to determine the correlations between clinicopathological characteristics and expression of this molecule.We assessed the levels of ETS-1 in a total of 96 laryngeal specimens of varying degrees of dysplasia, microinvasive squamous carcinoma (8), and invasive squamous carcinoma (60), using normal mucosal epithelium (10) as a positive control. The relationship between ETS-1 expression and clinicopathological parameters of laryngeal carcinoma was also analyzed.We found a significantly higher ETS-1 expression in invasive laryngeal squamous cell carcinomas than in dysplasia (P< 0.001). A correlation between ETS-1 expression scores and grade was detected - T factor, stage, cartilage invasion, lymph node metastasis, as well as depth of invasion in laryngeal tumors.Our study is the first to demonstrate that ETS-1 expression is significantly increased in invasive carcinoma, but it is absent in low-moderate grade laryngeal dysplasia and non-neoplastic laryngeal mucosa. This data suggest that ETS-1 expression may play an important role in tumor invasion, and may function in the initiation of the invasive process in laryngeal squamous cell carcinoma. © 2011 Elsevier GmbH.