Locally advanced breast cancer is breast cancer that has spread to tissue near the breast, but not to distant locations in the body (such as bones or the brain). A study found that Herceptin (chemical name: trastuzumab) given in combination with chemotherapy BEFORE surgery for HER2-positive locally advanced breast cancer improves survival without the breast cancer coming back (called "disease-free survival"). Treatments given before surgery are called neoadjuvant treatments. These results were presented at the 2008 San Antonio Breast Cancer Symposium.
Herceptin is a targeted therapy medicine commonly used AFTER surgery to treat HER2-positive breast cancers. HER2-positive cancers have too many copies of the HER2/neu gene that makes too much of the HER2 protein. About 1 out of every 4 breast cancers is HER2-positive. HER2-positive breast cancers tend to be more aggressive than HER2-negative breast cancers.
In this study, called the NOAH trial, half of 228 women diagnosed with HER2-positive locally advanced breast cancer got standard chemotherapy treatments before surgery. The other half of the women got standard chemotherapy treatments AND Herceptin before surgery. Because all the breast cancers were HER2-positive, all of the women were treated with Herceptin after surgery.
- 89% of the women who got chemotherapy AND Herceptin before surgery got benefits from the treatment, compared to 77% of the women who got chemotherapy with no Herceptin before surgery.
- When surgery was done, evidence of cancer was gone in 43% of the women who got chemotherapy AND Herceptin before surgery, compared to only 23% of the women who got chemotherapy with no Herceptin before surgery. After neoadjuvant treatment, doctors call no signs of cancer at surgery a "complete pathologic response."
- The women who got chemotherapy AND Herceptin before surgery were 45% more likely to be alive without the cancer coming back or growing 3 years after surgery compared to the women who got chemotherapy with no Herceptin before surgery.
- Overall survival was better for the women who got chemotherapy AND Herceptin before surgery compared to the women who got chemotherapy with no Herceptin before surgery. Still, this difference was small and could have been due to chance.
Most of the women who got Herceptin before surgery didn't have any serious side effects. Herceptin is given intravenously and may cause flu-like symptoms in about 40% of the people who receive it. Side effects are usually less severe after the first treatment. There is also a 5% to 30% risk that Herceptin can damage the heart's ability to pump blood effectively. The risk of serious heart damage goes up when Herceptin is given with other chemotherapy medicines known to cause heart damage. Adriamycin (chemical name: doxorubicin) is a chemotherapy medicine that can cause heart damage. In this study, 95% of the women who got Herceptin before surgery had no or very little effect on their hearts from the Herceptin.
Based on these results, adding Herceptin to the treatment plan before surgery for HER2-positive locally advanced breast cancer may make sense for many women. If you've been diagnosed with HER2-positive locally advanced breast cancer, Herceptin will likely be a part of your treatment plan after surgery. Consider talking to your doctor about this study and whether combining Herceptin with chemotherapy BEFORE surgery is a good choice for you. Together you and your doctor can decide on the best treatment based on your unique situation.
Visit the Breastcancer.org Targeted Therapies section to learn more about Herceptin and other targeted therapies used to treat breast cancer.