Prognostic significance of p53, bcl-2, and bax protein expression in laryngeal squamous cell carcinoma: a multivariate analysis

Background and objective. Conventional clinicopathologic parameters do not accurately reflect the clinical outcome of patients with head and neck carc inoma. The establishment of additional prognostic factors that may give ins ight into the biologic features of a tu mor is therefore an essential goal. The present study analyses the expression patterns of p53, bcl-2, and bax with regard to their relationships with conventional tumor parameters and t o their prognostic significance in patients with laryngeal squamous cell ca rcinoma. Patients/methods. Paraffin-embedded tissue sections of 88 primary laryngeal squamous cell carcinomas diagnosed and treated between 1986 and 1996 were investigated for p53, bcl-2, and bax protein expression by immunohistochemi stry. The mean follow-up time was 45.9 months. Results. Bcl-2 immunoreactivity was positively correlated with an advanced clinical stage, a high T category, regional lymph node metastasis, and a hi gh histological grading. Significant relationships between clinicopathologi c parameters and p53 or bax expression were not detectable. The age of the patients, advanced disease, positive bcl-2 expression, and a high level of p53 expression were significantly associated with shortened disease-specifi c survival in univariate analysis. In multivariate analysis, age, clinical stage,and p53 expression had independent prognostic value. Conclusions. Although expression of p53 and bcl-2 was found to be clinicall y relevant in univariate analysis, only p53 but not bcl-2 was an independen t predictor of patient outcome. This superiority of p53 in multivariate ana lysis points to its central role within cell cycle and death regulation, wi th which it influences two important parameters of tumor progression.