Prognostic value of p53 protein expression for patients with gastric cancer - a multivariate analysis

Mutations in the p53 gene, one of the most common genetic alterations in hu man cancer, are implicated in tumorigenesis and tumour progression. Althoug h p53 protein expression appears to be correlated to prognosis in patients with malignancy, its prognostic role in gastric cancer has remained controv ersial. We examined the clinical significance of p53 overexpression in 427 patients with gastric cancer, using multivariate analysis. Tumour sections of gastric cancer tissues from these 427 Japanese patients were stained imm unohistochemically with monoclonal antibody PAb1801. The presence of p53 ex pression was statistically compared with clinicopathological features and p ostoperative survival, using univariate and multivariate analyses. p53 expr ession was detected in 38.6% (165 out of 427) of these gastric cancers and immunoreactivity was not observed in normal mucosa adjacent to the tumour. A higher rate of p53 detection was observed among large tumours and in thos e with a prominent depth of invasion, lymphatic and vascular invasion and l ymph node involvement. Prognosis was significantly worse for patients with p53-positive-staining tumours. The 5-year survival rate was 62.5% for patie nts with p53-negative tumours and 43.3% for those with positive malignancie s. p53 expression was a significant prognostic factor for node-positive gas tric cancers in subjects undergoing treatment with curative resection, as a ssessed by Cox regression analysis. Thus, the expression of p53 was closely related to the potential for tumour advance and a poorer post-operative pr ognosis for patients with gastric cancer.