Expression of p53 and p21 are independent prognostic factors in patients with serosal invasion by gastric carcinoma.

To evaluate whether the expression of p53 and that of p21 are independent prognostic factors in patients with advanced gastric cancer, we investigated clinicopathological factors and the expression of p53 and p21 in 158 patients with gastric cancer that had invaded the serosa and who had undergone curative gastrectomy. In multivariate survival analysis of 156 surviving patients, we evaluated the size of the tumor, lymph node metastasis, venous invasion, lymph node dissection, expression of p53, and expression of p21 as independent prognostic factors. Moreover, we divided patients into four groups according to the expression of p53 and p21 in their tumors [group A, p53-/p21-, N = 40 (one died within 30 days of surgery); group B, p53-/p21+, N = 23; group C, p53+/p21-, N = 58; and group D, p53+/p21+, N = 37 (one died within 30 days of surgery)]. The 5- and 10-year survival rates of 39 patients in group A were 71.7% and 64.3%, those of 23 patients in group B were 81.4% and 81.4%, those of 58 patients in group C were 35.6% and 30.2%, and those of 36 patients in group D were 67.9% and 60.7%. The prognosis of patients in group C was poorer than that of patients in the other three groups. This result indicates that the evaluation of the expression of both p53 and p21 expression might provide prognostic information that is more accurate than that provided by evaluation of the expression of p53 alone.