CLINICAL RELEVANCE OF P53 INDEX AND EXPRESSION OF PROLIFERATING CELL NUCLEAR ANTIGEN AND KI-67 IN GASTRIC-CANCER

The prognostic value of the immunohistochemical expression of p53 prot ein, proliferating-cell nuclear antigen (PCNA) and Ki-67 antigen was e valuated in a series of 116 stage I-II gastric cancer patients. The st aining for p53 protein (staining frequency and intensity) in malignant cells was expressed as a p53 index. Similarly, the staining frequency and intensity for PCNA and Ki-67 were evaluated. The p53 index was in dependent of the stage and differentiation grade, but significantly re lated to DNA ploidy, S-phase fraction and mitotic activity. A high p53 index was a sign of inferior survival, compared to a low or intermedi ate index. p53-negative tumours were also associated with poor surviva l. In a multivariate analysis, only the depth of tumour infiltration a nd the presence of nodal metastases were independent prognostic factor s in stage I-II gastric cancer. PCNA expression and Ki-67 antigen expr ession were not related to the stage, ploidy, proliferative activity o r p53 expression, and they had no impact on survival. The results indi cate that p53 protein expression may be of prognostic significance in gastric cancer, while PCNA and Ki-67 antigen expression have no predic tive value.