Prognostic significance of the coexpression of p53 protein and c-erbB2 in breast cancer

Background The expressions of p53 protein and c-erbB2 have been thoroughly analyzed as prognostic factors for breast cancer. However, the prognostic significance of the coexpression of p53 protein and c-erbB2 remains controversial. Methods The immunohistochemical expression of p53 protein and c-erbB2 was evaluated in 242 women with breast cancer. Results According to the combination of p53 protein and c-erbB2, a group negative for both (125 cases), a group positive for either one of these two parameters (99 cases) and a group positive for both (18 cases) were identified. The group positive for one factor had a significantly (P = 0.0045) worse disease-free survival (DFS) than the group negative for both, while the group positive for both had a significantly (P = 0.0023) worse DFS than the group positive for one factor. A multivariate analysis indicated that the relative risk of p53 protein alone and cerbB2 alone was 2.18 and 2.93, respectively, while the relative risk of the group positive for one factor and the group positive for both was 2.29 and 6.37, respectively . Conclusions Breast cancer with a coexpression of p53 protein and c-erbB2 was thus found to have a more significant prognostic value than those with a positive expression for either of these two biological parameters, while the prognostic significance of these two parameters themselves remained independent of each other.