Blood levels of epidermal growth factor receptor (EGFR) may be elevated in women up to 17 months prior to a diagnosis of breast cancer. These findings were recently presented at the American Association for Cancer Research 101st Annual Meeting.
In an attempt to improve survival by detecting breast cancer at an earlier stage, researchers are evaluating potential biomarkers of the disease. Levels of certain proteins in the blood, for example, may be higher in women with breast cancer than in women without breast cancer. If these markers reliably distinguish women with and without breast cancer, and if the markers can be identified early in cancer development (before the cancer would typically be diagnosed clinically), then they may contribute to the early detection of breast cancer.
In the current study, researchers first evaluated blood samples from 420 women with estrogen receptor-positive breast cancer and a set of matched controls (women without breast cancer). For the women with breast cancer, blood had been collected up to 17 months prior to cancer diagnosis. Biomarkers that appeared promising at this first stage (that appeared to distinguish women with and without breast cancer) were then further evaluated in a separate set of women with and without breast cancer.
- EGFR levels were significantly elevated in women who developed breast cancer compared with controls.
- Women with the highest levels of EGFR had a 2.9-fold increased risk of developing breast cancer compared with women with the lowest EGFR levels.
- In women who used estrogen plus progestin hormone therapy, high EGFR levels were associated with a ninefold increased risk of developing breast cancer.
Although the results of this study did not indicate that EGFR levels were sufficient to be used as a sole predictor of breast cancer, the researchers were optimistic that “there may indeed be detectable changes of proteins in blood within two years of making a clinical breast cancer diagnosis.” This type of research continues to hold promise.
 Pitteri SJ, Amon LM, Buson TB, et al. Elevated plasma levels of epidermal growth factor receptor prior to diagnosis of breast cancer in preclinical specimens from the Women’s Health Initiative Observational Study. Proceedings from the 101st Annual Meeting of the American Association for Cancer Research. April 17-21, 2010. Abstract 4815.