Abstract S3-06: A phase III trial evaluating pCR in patients with HR+, HER2-positive breast cancer treated with neoadjuvant docetaxel, carboplatin, trastuzumab, and pertuzumab (TCHP) +/- estrogen deprivation: NRG Oncology/NSABP B-52

Background:Preclinical evidence has shown that in xenograft models with estrogen receptor (ER)+/HER2+ breast cancer, signaling through the ER pathway can be enhanced in the presence of anti-HER2 treatment and lead to treatment resistance. Concurrent targeting of ER and HER2 has led to enhanced treatment efficacy and complete tumor disappearance. We hypothesized that targeting ER with endocrine therapy concurrently with chemotherapy plus dual HER2 inhibition will not be antagonistic and can overcome ER-mediated resistance and result in higher pCR as neoadjuvant treatment of ER+/HER2+ breast cancer. NRG Oncology/NSABP B-52 is a phase III, multicenter, randomized neoadjuvant therapy trial designed to determine whether the addition of estrogen deprivation to neoadjuvant therapy consisting of docetaxel, carboplatin, trastuzumab, and pertuzumab (TCHP+Est-Dep) yields a greater rate of pCR (breast and nodes) than TCHP alone.Methods:A total of 315 patients (pts) were randomly assigned between January 15, 2014 and March 17, 2016 to receive neoadjuvant therapy consisting of TCHP with or without estrogen deprivation therapy. Pts with locally advanced, hormone receptor-positive, HER2+ invasive breast cancer with no evidence of metastatic disease were eligible. Premenopausal women randomized to estrogen deprivation therapy received ovarian function suppression with goserelin (LHRH agonist) or equivalent plus an aromatase inhibitor (AI). Postmenopausal women received an AI. The determinatio...
Source: Cancer Research - Category: Cancer & Oncology Authors: Tags: General Session Abstracts Source Type: research