Without HER2-targeted therapy, HER2-positive breast cancer has a higher risk of recurrence than HER2-negative breast cancer, even when the breast cancer is small (1 cm or less); this raises the possibility that even women with very small HER2-positive breast cancers may benefit from a HER2-targeted therapy such as Herceptin® (trastuzumab). These results were presented at the 2008 San Antonio Breast Cancer Symposium.
The human epidermal growth factor receptor 2 (HER2) is part of a biological pathway involved in growth and spread of cancer cells. Several types of cancers overexpress HER2, including approximately 15-20% of breast cancers. These cancers are referred to as HER2-positive.
Herceptin is a drug that targets HER2 and helps to slow or stop the spread of cancer cells that overexpress HER2. Herceptin has been shown to improve treatment outcomes among women with both early-stage and advanced HER2-positive breast cancer.
A question that has remained uncertain is the need for HER2-targeted therapy among women with small breast cancers (less than 1 cm). To explore the behavior of small breast cancers in the absence of Herceptin, researchers at the M. D. Anderson Cancer Center evaluated the wp_posts of 965 breast cancer patients who were treated between 1990 and 2002. All of the patients had tumors that measured 1 cm or less, and none had received adjuvant chemotherapy or Herceptin.
- By the end of five years, 6% of women with HER2-negative breast cancer had developed a recurrence compared with 23% of women with HER2-positive breast cancer.
The results of this study suggest that even small HER2-positive breast cancers have an increased risk of recurrence. Consideration of adjuvant treatment with a HER2-targeted therapy such as Herceptin may be important for all women with HER2-positive breast cancer, regardless of the size of the cancer. It should be noted, however, that the current study did not assess the effectiveness of HER2-targeted therapy in women with small, HER2-positive breast cancer.
Reference: M. D. Anderson Cancer Center news release. Early stage, HER2 positive breast cancer patients at increased risk of recurrence. Largest study of its kind finds subset of women that may need additional therapy. Available at: Accessed December 12, 2008.
Copyright © 2018 CancerConnect. All Rights Reserved.