Incidence of Late Relapses in Patients With HER2-Positive Breast Cancer Receiving Adjuvant Trastuzumab: Combined Analysis of NCCTG N9831 (Alliance) and NRG Oncology/NSABP B-31

J Clin Oncol. 2019 Dec 10;37(35):3425-3435. doi: 10.1200/JCO.19.00443. Epub 2019 Oct 17.


Purpose: Recent trials have shown potential benefit of extended adjuvant endocrine therapy and relatively high risk of recurrence (RoR) after 5 years in hormone receptor-positive (HR+) human epidermal growth factor receptor 2-negative (HER2-) breast cancer. Although risk of late relapse in HR+ HER2- breast cancer is fairly well defined, the risk in HER2-positive (HER2+) breast cancer treated with adjuvant trastuzumab-based chemotherapy remains largely unknown.

Methods: We included 3,177 patients with HER2+ breast cancer treated with adjuvant chemotherapy alone or with trastuzumab from the North Central Cancer Treatment Group N9831 ( identifier: NCT00005970) and National Surgical Adjuvant Breast and Bowel Project B-31 ( identifier: NCT00004067) trials.

Results: Overall, HR+ breast cancer was significantly associated with improved recurrence-free survival (RFS) during the first 5 years (hazard ratio, 0.65; 95% CI, 0.56 to 0.77; P < .001). Among patients treated with trastuzumab, cumulative hazard for RFS was lower in patients with HR+ HER2+ breast cancer during the first 5 years (10.96% v 17.48%; hazard ratio, 0.60; 95% CI, 0.45 to 0.79; P < .001). However, there was no significant difference in RFS based on HR status during years 5 to 10 (hazard ratio, 1.32; 95% CI, 0.93 to 1.88; P = .12). A comparable degree of trastuzumab benefit was observed in HR+ and HR- breast cancers ( P for interaction = .87). Furthermore, we observed low RoR in years 5 to 10 among patients with HR+ HER2+ breast cancer: 3.23% in patients without lymph node involvement (N0) and 6.39% in patients with involvement of one to three lymph nodes (N1).

Conclusion: The benefit of adjuvant trastuzumab persists for a long time. A distinct pattern of recurrence was observed between HR+ and HR- HER2+ disease but with similar degree of benefit from adjuvant trastuzumab. RoR in years 5 to 10 in HR+ HER2+ breast cancer is low, particularly in patients with N0 or N1 disease.

Publication types

  • Clinical Trial, Phase III
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antineoplastic Combined Chemotherapy Protocols / adverse effects*
  • Breast Neoplasms / drug therapy*
  • Breast Neoplasms / metabolism
  • Breast Neoplasms / pathology
  • Cyclophosphamide / administration & dosage
  • Doxorubicin / administration & dosage
  • Female
  • Follow-Up Studies
  • Humans
  • Incidence
  • Middle Aged
  • Neoplasm Recurrence, Local / chemically induced
  • Neoplasm Recurrence, Local / diagnosis
  • Neoplasm Recurrence, Local / epidemiology*
  • Paclitaxel / administration & dosage
  • Prognosis
  • Receptor, ErbB-2 / metabolism*
  • Survival Rate
  • Trastuzumab / administration & dosage
  • United States / epidemiology
  • Young Adult


  • Doxorubicin
  • Cyclophosphamide
  • ERBB2 protein, human
  • Receptor, ErbB-2
  • Trastuzumab
  • Paclitaxel

Associated data