This study investigated the prognostic significance of thymidine phosphorylase (TP) and p53 expression in 96 surgically resected primary esophageal squamous cell carcinomas. Expression was assessed using immunohistochemical staining methods. Prognostic values were determined by multivariate analysis using Cox's proportional hazards model. Although TP expression was not correlated with p53 expression, it was associated with genetic alteration of the latter. In univariate analysis, TP expression emerged as a significant prognostic factor but p53 expression did not. However, in multivariate analysis, despite TP not being a significant independent predictor of survival, co-expression of TP together with p53 did represent a statistically significant prognostic factor.