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).
Miguel Martín, MD, PhD, of the Gregorio Marañón Institute and GEICAM, discusses phase III study findings that showed no improvement in progression-free survival with palbociclib plus endocrine therapy vs capecitabine in patients with hormone receptor–positive/HER2-negative metastatic breast cancer whose disease progressed on aromatase inhibitors—although the drug combination was generally better tolerated than capecitabine (Abstract GS2-07).
Hope S. Rugo, MD, of the University of California San Francisco Comprehensive Cancer Center, discusses trial data on margetuximab plus chemotherapy, which improved progression-free survival in patients with previously treated HER2-positive metastatic breast cancer when compared with trastuzumab plus chemotherapy. Maturing data comparing overall survival also provides new insights (Abstract GS1-02).
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).
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).
Rowan T. Chlebowski, MD, PhD, of the Lundquist Institute at Harbor-UCLA Medical Center, discusses the long-term influence of using estrogen plus progestin or estrogen alone on breast cancer incidence and mortality (Abstract GS5-00).
