Abstract OT2-03-02: DI study: Decision impact of the NanoString® Technologies Prosigna™ in early breast cancers

Abstract

Abstract Backgrounds: More than a decade of research, clinical studies, and peer reviewed publications support the value of molecular subtyping based on gene expression analyses to assess prognosis and treatment options for patients with early-stage breast cancer. Therefore, genomic assays are now being introduced to supplement the conventional diagnostic tools. Prosigna is a standardized test that measures the expression levels of 50 classifier genes in formalin-fixed, paraffin-embedded (FFPE) breast tumor tissue samples and provide a subtype classification based on the fundamental biology of individual patient's tumor (referred to as molecular subtyping), as well as a prognostic score (referred to as risk of recurrence (ROR) score) that predicts the probability of cancer recurrence over 10 years. The primary objective of this study is to assess the extent to which Prosigna affects the medical oncologist's treatment recommendations regarding adjuvant chemotherapy and actual treatments received for patients with early-stage breast cancer. Changes will include hormonal therapy alone, hormonal therapy plus chemotherapy, and changes in types of chemotherapy if chemotherapy was recommended before and after the test. Secondary objectives will be to elicit information on investigators' confidence in the recommendations before and after the test, and by cancer recurrence risk groups, rate of chemotherapy related adverse events stratified by administration of chemotherapy, and patients' decisional conflict status, anxiety levels, and functional status before and after Prosigna results. Multicentric prospective study. Prosigna will be performed on operative piece for all consecutively postmenopausal women matching the inclusion criteria and having signed an informed consent. Data on patient demographics, disease status, intended cancer-specific postoperative management before and after the test, tests results, investigators and patients' confidence in the treatment and in the test, will be recorded in the inclusion visit, after the tests results and 6 month post-assay. Inclusion criteria: Postmenopausal patients with resected node-negative, estrogen-receptor-positive, HER2-negative (by the local laboratory) early-stage invasive breast cancer (T1-T2, N0, pN0 (i+), pN1 (micrometastatic), M0), able to give consent, eligible for treatment of breast cancer with adjuvant chemotherapy and with ECOG performance status of 0 or 1. Statistical methods: The clinical and demographic characteristics of the study sample will be described using mean, median, standard deviation, and range for continuous/ordinal variables and frequency and proportion for categorical variables. Bivariate plots and crosstabs will be performed to inspect bivariate associations between variables. The proportion of patients for whom the physicians' choice of treatment changed from baseline to follow-up will be calculated along with the 95% confidence interval. The change in investigator confidence in treatment recommendations before and after Prosigna results were known will be analyzed by calculating the mean and 95% CI for the question regarding whether a physician is more confidence in treatment recommendation after ordering Prosigna. 47 patients have been included on 200 scheduled. Citation Format: Lerebours F, Hequet D, Guinebretière J-M, Roulot A, Callens C, Gentien D, Penault-LLorca F, Zilberman S, Salmon R, Foa C, Berseneff H, Huchon C, Katz G, MacDonald M, Morel P, Bieche I, Dubot C, Rouzier R. DI study: Decision impact of the NanoString® Technologies Prosigna™ in early breast cancers. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr OT2-03-02.