NSABP B-47/NRG Oncology Phase III randomized trial comparing adjuvant chemotherapy with or without trastuzumab in high-risk invasive breast cancer negative for HER2 by FISH and with IHC 1+ or 2 Journal Article uri icon
  • PURPOSE: Adjuvant trastuzumab reduces invasive breast cancer (IBC) recurrence and risk for death in patients with HER2-amplified or overexpressing IBC. A subset of patients in the landmark trastuzumab adjuvant trials who originally tested HER2-positive but were HER2-negative by central HER2 testing appeared to possibly benefit from trastuzumab. The objective for the NSABP B-47 trial was to determine whether the addition of trastuzumab to adjuvant chemotherapy (CRx) would improve invasive disease-free survival (IDFS) in patients with HER2-negative breast cancer. PATIENTS AND METHODS: A total of 3,270 women with high-risk primary IBC were randomly assigned to CRx with or without 1 year of trastuzumab. Eligibility criteria included immunohistochemistry (IHC) score 1+ or 2+ with fluorescence in situ hybridization ratio (FISH) < 2.0 or, if ratio was not performed, HER2 gene copy number < 4.0. CRx was either docetaxel plus cyclophosphamide or doxorubicin and cyclophosphamide followed by weekly paclitaxel for 12 weeks. RESULTS: At a median follow-up of 46 months, the addition of trastuzumab to CRx did not improve IDFS (5-year IDFS: 89.8% with CRx plus trastuzumab [CRxT] v 89.2% with CRx alone; hazard ratio [HR], 0.98; 95% CI, 0.76 to 1.25; P = .85). These findings did not differ by level of HER2 IHC expression, lymph node involvement, or hormone-receptor status. For distant recurrence-free interval, 5-year estimates were 92.7% with CRxT compared with 93.6% for CRx alone (HR, 1.10; 95% CI, 0.81 to 1.50; P = .55) and for overall survival (OS) were 94.8% with CRxT and 96.3% in CRx alone (HR, 1.33; 95% CI, 0.90 to 1.95; P = .15). There were no unexpected toxicities from the addition of trastuzumab to CRx. CONCLUSION: The addition of trastuzumab to CRx did not improve IDFS, distant recurrence-free interval, or OS in women with non-HER2-overexpressing IBC. Trastuzumab does not benefit women without IHC 3+ or FISH ratio-amplified breast cancer.

  • Link to Article
    publication date
  • 2020
  • published in
  • Breast Cancer
  • Chemotherapy
  • Clinical Trials
  • Drugs and Drug Therapy
  • Randomized Controlled Trials
  • Risk Factors
  • Additional Document Info
  • 38
  • issue
  • 5