Abstract

Aims—To investigate the expression of α, β, and γ catenins in oropharyngeal and hypopharyngeal squamous cell carcinoma and their relations to each other, as well as to clinical data, tumour differentiation, and prognosis.

Methods—Primary tumours for analysis were obtained from 138 patients diagnosed with squamous cell carcinoma of the oropharynx or hypopharynx between 1975 and 1998 in eastern Finland. Immunohistochemistry was used to evaluate the expression of α, β, and γ catenins. The expression patterns of all catenins were related to clinical data and survival.

Results—The expression patterns of all three catenins were significantly interrelated. Reduced γ catenin expression was significantly associated with poor histological differentiation. No association was found between α or β catenin expression and clinicopathological characteristics. In univariate analysis, patients whose tumours had nuclear β catenin expression had shorter overall survival than patients with no nuclear expression. In Cox multivariate analysis, nuclear β catenin expression, tumour status (T class), and Karnofsky performance index were independent prognostic factors of overall survival.

Conclusions—Reduced expression of γ catenin is associated with dedifferentiation in primary squamous cell carcinoma of the oropharynx and hypopharynx. The fact that nuclear β catenin expression independently predicts short overall survival suggests that it might be a valuable prognostic marker in pharyngeal squamous cell carcinoma.