Clinical relevance of p53 and bcl-2 protein over-expression in laryngeal squamous-cell carcinoma.

We investigated immunohistochemically the clinical relevance of the over-expression of the apoptosis-regulating proteins p53 and bcl-2 in a homogeneous series of 149 laryngeal squamous-cell carcinomas. p53 was over-expressed in 75 cases and bcl-2 in 39 cases. p53 and bcl-2 co-expression was found in 21 cases. p53 and bcl-2 immunoreactivity was significantly associated with poor histological differentiation and lymph-node metastases. Moreover, a significant statistical correlation was found between bcl-2 expression, supraglottic tumor site and advanced disease stage. p53/bcl-2 co-expression was significantly associated with poor differentiation, tumor extension, the presence of lymph-node metastases and advanced clinical stage. Univariate analysis showed that a lower probability of survival was significantly associated with supraglottic site, tumor extension, advanced clinical stage and p53/bcl-2 co-expression, but not with p53 or bcl-2 considered separately. In multivariate analysis, only tumor extension and supraglottic site retained their prognostic value. Our data suggest that clinical staging remains the most reliable predictive indicator of survival in patients with laryngeal carcinoma.