Expression of p21 (waf1/cip1/sdi1), but not p53 protein, is a factor in the survival of patients with advanced gastric carcinoma.

The authors examined whether expression of p21 (waf1/cip1/sdi1) and p53 protein was related to survival, rates in patients with advanced gastric carcinoma. The expression of p21 and p53 protein was analyzed by immunohistochemistry in 93 patients with advanced gastric carcinoma with serosal invasion and lymph node metastasis. All patients underwent curative surgery. The probability of survival was calculated by the Kaplan-Meier method and compared by the generalized Wilcoxon test. Various levels of p21 and p53 immunoreactivities in carcinoma cells were detected in 30 (32%) and 60 (65%), respectively, of 93 samples. There was no correlation between p21 and p53 expression. The 5-year survival rate of patients with p21 expression was 69.4%, which was significantly better than that of patients without p21 expression (38.1%; P < 0.05). However, p53 protein expression did not correlate with patient survival. Expression of p21 protein may be a better prognostic factor than p53 protein expression in patients with advanced gastric carcinoma.