p53 protein expression in resected invasive esophageal cancer

Many studies have reported the increased expression of p53 protein in various human malignancies and its accumulation have been considered an intermediate biomarker in multistage carcinogenesis. This study was designed to evaluate p53 expression by immunohistochemistry using Dako p53, D0-7 monoclonal antibody in 33 resected invasive squamous cell esophageal cancers (SqCC). The relationship between p53 immunoreactivity and clinicopathologic parameters was determined by the Chi-square test and Student's t test. p53 protein overexpression (more then 10% positive staining cancer cells) was found in 15 out of 33 (45%) tumors. Positive test was found in 38% cases in Stage IIA, 57% in Stage IIB, 45% in Stage III and 50% cases in Stage IV. p53 overexpression was observed in 48% of tumors with lymph nodes metastases, and 41% of tumors without lymph nodes metastases. In respect of tumor differentiation, cases graded as G1, G2 and G3 were positive in 50%, 50% and 40%, respectively. Thirteen per cent of patients with p53 protein overexpression and 16% of patients without p53 protein overexpression survived more than 3 years. There was no correlation between p53 overexpression and stage, tumor differentiation, lymph nodes metastases, and patients survival. In conclusion our results showed that p53 overexpression did not correlate with clinicopathologic feature of invasive SqCC of the esophagus and p53 protein overexpression was unsuitable for predicting the outcome of patients after surgical resection.