1. Home>
2. Specialties>
3. General Medicine>
4. Summary and Comment

Trastuzumab for HER2-Positive Breast Cancer

In these randomized studies of women with nonmetastatic disease, those who received adjuvant chemotherapy plus trastuzumab had a better chance of 2-year disease-free survival than did those who received adjuvant chemotherapy alone.

Breast cancers with amplification or overexpression of the human epidermal growth factor receptor 2 (HER2) are particularly aggressive. Trastuzumab (Herceptin), a monoclonal antibody against HER2, has been shown to benefit patients with HER2-positive metastatic breast cancer. Now, researchers report outcomes from three randomized studies of adjuvant therapy with trastuzumab, involving nearly 7000 women with HER2-positive tumors and no evidence of distant metastases. Most patients had one or more positive axillary nodes. All patients underwent surgery, and most had radiation therapy.

Key findings were:

• In a comparison between adjuvant chemotherapy alone and adjuvant chemotherapy followed by a 1-year course of trastuzumab (given intravenously once every 3 weeks), the estimated rate of 2-year disease-free survival was significantly greater in the trastuzumab group than in the control group (86% vs. 77%). This study was industry-sponsored.
  
• In a comparison between adjuvant chemotherapy alone and adjuvant chemotherapy plus an overlapping 1-year course of trastuzumab (given intravenously once weekly), the estimated rate of 3-year disease-free survival was significantly greater in the trastuzumab group than in the control group (87% vs. 75%). In addition, the 3-year mortality rate was significantly lower in the trastuzumab group. These data were taken from two studies, each supported by the National Cancer Institute and the maker of trastuzumab.
  
• Severe congestive heart failure, a known side effect of trastuzumab, occurred in 0.5% to 4.1% of trastuzumab recipients (patients with histories of heart disease were excluded from these trials).
  

Comment: In these studies, trastuzumab was associated with substantial reductions in disease recurrence among women with HER2-positive breast cancer. An editorialist calls these findings "stunning" and states that trastuzumab now should be included in adjuvant therapy regimens for most patients with HER2-positive tumors. Trastuzumab's cardiotoxicity precludes its use in certain patients, however.

— Allan S. Brett, MD

Published in Journal Watch General Medicine October 21, 2005

Citation(s):

Piccart-Gebhart MJ et al. Trastuzumab after adjuvant chemotherapy in HER2-positive breast cancer. N Engl J Med 2005 Oct 20; 353:1659-72.

• Original article (Subscription may be required)
• Medline abstract (Free)

Romond EH et al. Trastuzumab plus adjuvant chemotherapy for operable HER2-positive breast cancer. N Engl J Med 2005 Oct 20; 353:1673-84.

• Original article (Subscription may be required)
• Medline abstract (Free)

Hortobagyi GN. Trastuzumab in the treatment of breast cancer. N Engl J Med 2005 Oct 20; 353:1734-6.

• Original article (Subscription may be required)
• Medline abstract (Free)