A 10-year Survival Analysis towards Molecular and Clinical Factors in Taiwan Breast Cancer Patients

Background: Breast cancer is one of the major cancers responsible for female deaths in recent years. Since both molecular and pathological aspects of breast tumors are quite diverse among different races and tumor histological types, this study was designed to investigate the relationship of several molecular markers with other known prognostic factors in Taiwanese women with breast infiltrative ductal carcinoma. Methods: In total, 146 patients with primary, resectable breast cancer were consecutively recruited into this study from 1999. Seventy-six patients remained available for analysis due to a long (＞ 10 years) follow-up period. All patients received a modified radical mastectomy by a single surgeon. After surgery, concentrations of the estrogen receptor (ER) and progesterone receptor (PR) and the expression of human epidermal growth factor receptor (HER)-2/neu were determined by an immunohistochemical analysis, and patients were treated according to standard protocols. Only patients with infiltrative ductal carcinoma were analyzed. Results: Twenty-one of 76 patients (27.6%) with infiltrative ductal carcinoma were found to be overexpressing HER-2/neu. Compared to patients without HER- 2/neu overexpression, patients with HER-2/neu overexpression were associated with advanced pathological stages, less ER- and PR-positivity, and shorter disease-free survival. In the Kaplan- Meier analysis, survival of patients overexpressing HER-2/neu was similar to that of patients without HER-2/neu overexpression. Moreover, neither hormone receptor (ER or PR) status was prognostic for survival. The two groups of patients were also similar in age, nodal status, and tumor size. Conclusions: Compared to previous reports, HER-2/neu is as an effective prognostic marker in breast infiltrative ductal carcinoma of Taiwanese women. Results suggest that histological and ethnic factors should be considered in future cancer studies.