Objective: Trastuzmab combined therapy has been recommended as standard therapy for HER-2-positive breast cancer. However, more than 70% HER-2-positive cases do not recur and might thus be with overtreatment risk. The aim of this study was to explore the significance of TIMP-1 and nm-23 expression in identifying the good prognosis subtype in HER-2-positive breast cancer.
Methods: One hundred and sixty-five cases of HER-2-positive breast cancer treated in Tianjin Medical University Cancer Hospital from Jan. 1987 to Dec. 1988 were studied. Expressions of TIMP-1 and nm-23 were detected by immunohistochemistry and the correlation with clinicopathologic characteristics and long-term outcome was analyzed.
Results: 53.3% (88/165) of TIMP-1 and 72.7% (120/165) of nm-23 expression were detected in the patients. The TIMP-1-negative patients classified as good prognosis group had a 10-year metastasis free survival (MFS) of 58.4% and 10-year overall survival (OS) of 68.8%, compared with the 10-year MFS of 43.2% (P = 0.041) and 10-year OS of 52.0% in the positive group (P = 0.020). The nm-23-positive patients classified as good prognosis group had a 10-year MFS of 54.2% and 10-year OS of 65.7%, compared with the 10-year MFS of 40.0% (P = 0.049) and 44.1% (P = 0.015) in the negative group. The multivariate analysis showed that expressions of TIMP-1 and nm-23, tumor size and lymph node involvement were independent prognostic factors.
Conclusions: In HER-2-positive breast cancer, TIMP-1 and nm-23 can be used to further distinguish between low-risk and high-risk subgroups, and they are independent factors in prognosis.