Ariella B. Hanker, PhD, of UT Southwestern Medical Center, discusses data showing that breast cancers expressing co-occurring HER2 and HER3 mutations may require the addition of a phosphoinositide 3-kinase alpha inhibitor to a HER2 tyrosine kinase inhibitor (Abstract GS6-04).
Terry P. Mamounas, MD, MPH, of Orlando Health UF Health Cancer Center, discusses 10-year results from NRG Oncology/NSABP B-42, which showed that, for postmenopausal women with hormone receptor–positive breast cancer who have completed previous adjuvant therapy with an aromatase inhibitor or with tamoxifen followed by an aromatase inhibitor, extended treatment with letrozole improved disease-free survival (Abstract GS4-01).
Ivana Sestak, PhD, of Queen Mary University of London and the Centre for Cancer Prevention, discusses study findings that confirm the prognostic ability of the Clinical Treatment Score at 5 years (CTS5) for late distant recurrence, specifically for patients older than 50 years and/or for those deemed to have intermediate- or high-risk hormone receptor–positive, HER2-negative, node-negative breast cancer. The CTS5 is less prognostic in women younger than 50 who received 5 years of endocrine therapy alone (Abstract GS4-03).
Rashmi K. Murthy, MD, of The University of Texas MD Anderson Cancer Center, discusses data on the efficacy and safety of tucatinib, trastuzumab, and capecitabine, a treatment regimen under investigation for patients with advanced HER2-positive metastatic breast cancer refractory to standard-of-care regimens (Abstract GS1-01).
Marie-Jeanne T.F.D. Vrancken Peeters, MD, PhD, of the Netherlands Cancer Institute, discusses an interim study analysis showing that ultrasound-guided core biopsies of the breast in patients with excellent response on MRI after neoadjuvant systemic therapy may not be accurate enough to safely select patients with pathologic complete response for omission of surgery (Abstract GS5-06).
Ian E. Krop, MD, PhD, of Dana-Farber Cancer Institute, discusses phase II trial findings on trastuzumab deruxtecan, a HER2-targeting antibody-drug conjugate, in patients with HER2-positive metastatic breast cancer who were previously treated with trastuzumab emtansine (Abstract GS1-03).
