The impact of 21-gene recurrence score (RS) scores on treatment decisions: Retrospective evaluation in Turkish early-stage breast cancer (BC) patients.

e11042 Background: The RS assay has been shown to quantify the likelihood of distant recurrence and also predict the magnitude of benefit from chemotherapy (CT) in women with estrogen receptor positive, node negative with BC. We planned to examine our experience about the effect of RS on treatment decisions in Turkish early BC patients (pts). Methods: We retrospectively reviewed the medical records of the pts whose tumor (tm) tissue has been sent for RS analysis from 8 different oncology centers. We noted the patient, tm, treatment-related characteristics and demographic information. Oncologists are requested to provide their treatment decision before and after the RS assay. Results: We identified 89 cases with a median age of 48 (27-73). Fifty-one pts were premenopausal. Seventy-five pts had breast conserving surgery, 86 pts had SLNB. Sixteen pts had T2 disease, 7 pts had N1 disease, 9 pts had nodal micrometastases. The percentage of grade 1/2/3 tms were 29/57/14% respectively. All tms were ER positive a...