Objective To study the relationship between lymph node metastasis and prognosis and the p53 gene mutation and expression of p53 protein in carcinoma and paracancerous tissues of the stomach.Methods The mutation of p53 gene and expression of p53 protein were examined by PCR-SSCP and immunohistochemical staining techniques.Results(1) The positive expression rate of p53 protein was 47.6% and 38.1% in carcinomas and paracanerous tissues,respectively.The expression of p53 protein reached to 52.8%.(2) The mutation rate of the exon 7 was 23.9% and 19.0% in paraffin-embedded carcinomas and paracancerous tissues,respectively.The mutation rate of exon 6 was 10.5% and 8.6% in paraffin-embedded carcinomas and paracancerous tissues,respectively.The mutation rate of exon 8,9 was 1.9% and 1.0% in paraffin-embedded carcinomas and paracancerous tissues,respectively.Conclusion In cases with lymph node metastasis,the mutation of p53 gene and expression of p53 protein was apparently increased,indicating that the mutation of exons in the development and progression of gastric carcinoma is an important factor.It also facilitates the metastasis of tumor.The mutation of p53 gene and high expression of p53 protein are not significantly different in carcinomas and paracancerous tissues of the stomach.