Prognostic Significance of p53 and Ki67 Proteins Expression in Greek Gastric Cancer Patients

Abstract Aim: The variability of prognosis of gastric cancer (GC) within a pathological stage necessitates the identification of subgroups of patients with a more aggressive disease. The role of p53 and Ki67 expression in gastric carcinoma is far from being fully established. The aim of the present study was to evaluate the expression of p53 and Ki67 in gastric cancer and correlate the findings with several clinicopathological features and prognosis. Materials and methods: Tissue samples from 93 patients treated by gastric resection for gastric carcinoma between 1996 and 2001 were used. Formalin-fixed paraffin-embedded tumors were studied by immunohistochemistry, using monoclonal antibodies to p53 and Ki67. The results were correlated with clinicopathological features and survival. Results: Stronger expression of p53 was related with tumor size greater than 5 cm and advanced stage. Stronger expression of Ki67 correlated with higher ratio of the number of metastatic lymph nodes to the total number of dissected lymph nodes (metastatic lymph node [MLN] ratio) and advanced stage. Moreover, p53 and Ki67 overexpression, tumor size greater than 5 cm, MLN ratio, depth of invasion, lymph node metastasis, stage III and IV and infiltrative macroscopic appearance were adverse prognostic factors. The levels of p53 and Ki67, the MLN ratio, the tumor size (above 5 cm) and the stage of the disease were identified as independent prognostic factors of survival. Conclusions: In gastric cancer, the expression of p53 and Ki67 provides significant information about prognosis. The routine evaluation of p53 and Ki67 levels could be a useful tool in identification of patient with more aggressive disease and contribute to a better therapeutic approach.