Expression of p53 and RE proteins in squamous cell carcinoma of the esophagus: Their relationship with clinicopathologic characteristics

Background: Cancer of the esophagus is one of the most malignant tumors and has a poor prognosis. The p53 and retinoblastoma (RB) genes are involved i n the regulation of cell population by suppressing cell proliferative activ ity. Our goal was to clarify whether expression of p53 and RE genes could b e prognostic factors in squamous cell carcinoma of the esophagus. Methods: Tumor samples taken from 73 patients undergoing subtotal esophagec tomy were immunohistochemically stained for the p53 and RE genes. An image analyzer was used for quantitative assessment of the staining, and clinicop athologic characteristics of those patients were investigated. Results: Patients in whom p53 expression was high had greater tumor diamete r, deeper tumor invasion, and worse prognosis compared with patients in who m p53 expression was low. Patients in whom RE expression was low had a high er incidence of lymph node metastasis and more advanced disease than did th ose in whom RE expression was high. The combination of p53 and RE expressio n revealed that the cases with high p53 and low RE expression had significa ntly worse survival rates and deeper tumor invasion compared with other gro ups. In various clinicopathologic parameters, (e.g., age, sex, tumor-diamet er, tumor type, location, differentiation, TNM classification, TNM stage) t umor type, tumor size, depth of invasion, lymph node involvement, distant m etastasis, and combined p53 and RE expression showed significant difference s in survival by univariate analysis. Among those six variables, only lymph node involvement showed an independent prognostic factor for survival (P = .0055) by multivariate analysis. Conclusions: The combination of p53 and RE expression is not a prognostic i ndicator in the surgical treatment of esophageal cancer.