Clinicopathologic Features And Survival Of Low ER-positive Breast Cancer

Objective: Low estrogen receptor-positive(ER-Positive 1%?9%)breast cancer in response to endocrine therapy is not clear,and there are also doubts about its application of endocrine therapy in the clinic.This study compared clinicopathological features and survival of ER-negative,ER-positive 1%?9%,ER-positive ?10%,and breast cancer,and related analysis was performed.Methods: A retrospective analysis of 862 patients with early breast cancer who were treated at the Breast Diseases Diagnosis and Treatment Center of Hebei Province from January 2012 to December 2012.Patients were divided into 3 groups based on ER expression status: group A represented ER-negative,group B represented ER-positive 1%?9%,and group C represented ER-positive ?10%.The clinicopathological characteristics(including age,lymph node status,tumor diameter,Ki-67,her-2,etc.)of the three groups were compared,and a simple survival analysis was performed.Results: Among the 862 breast cancer patients,194 were ER-negative(22.5%),25 were ER-positive 1%?9%(2.9%),and 643 were ER-positive ?10%(74.6%).The clinicopathological features including age,tumor size,nodal status,menopausal status,histology,adjuvant chemotherapy were similar among group A and group B.Compared with patients in group C,patients in group B had earlier stage,larger tumors,more HER-2 positive,higher expression rate of Ki-67,lower expression rate of PR,more susceptible to receive chemotherapy and less likely to accept endocrine therapy.Regardless of whether received endocrine therapy or not,the 7-years OS of the group A and group B were not significantly different(P = 0.971),and were worse than that of the group C(P = 0.026).Conclusions: The clinicopathological features of low ER-positive breast cancers were different from those of ER-positive ?10% breast cancers,and similar to those of ER-negative breast cancer.Low ER-positive in breast cancer patients benefit from endocrine therapy is not significant.