TPS654 Background: It is uncertain whether adjuvant chemotherapy is required in the treatment of postmenopausal women with hormone-responsive and intermediate risk breast cancer. The TAILORx and MINDACT trials are ongoing and utilize gene expression profiling in order to answer this question. We have initiated a new study to address this matter by using response to initial neoadjuvant endocrine therapy. The primary aim of this phase III study is to evaluate the necessity of using adjuvant chemotherapy for the treatment of postmenopausal breast cancer patients with node-negative, ER-positive and HER2-negative tumors who responded to neoadjuvant LET. Methods: Inclusion criteria are T1c-T2N0M0, ER-positive by IHC (<10%), HER2-negative, postmenopausal women under 75 years old and written informed consent. Lymph node positive patients as assessed by SLNB are excluded. Neoadjuvant LET is administered for 24-28 weeks before surgery. CR, PR or SD patients are then randomized into two arms receiving either chemotherapy plus LET for 4.5-5 years or LET alone for 4.5-5 years after surgery. If the primary tumor response is defined as PD before surgery, the treatment will be changed at the investigator's discretion (surgery, chemotherapy or other endocrine therapy, but these patients will be followed up). The primary endpoint is disease-free survival (DFS), and secondary endpoints are overall survival (OS), response rate of LET, pathological response, breast conserving surgery rate, DFS/OS by response rate of LET, safety, QOL and cost-effectiveness. This study utilizes a randomized selection design. The objective of this design is to select the arm with the better outcome. We also conduct an additional translational research and central pathological review of ER, PgR, HER2, and Ki67.Patient recruitment commenced in May 2008 and 803 patients were enrolled at the end of 2012. A total of 850 patients will be enrolled at the end of May 2013. This study is supported by Public Health Research Foundation. Clinical trial information: UMIN000001090.
0174 A phase III study of adjuvant endocrine therapy with or without chemotherapy for postmenopausal breast cancer patients who responded to neoadjuvant letrozole: Study design of the new primary endocrine-therapy origination study [NEOS (N-SAS BC06)]
