Breast cancer is a devastating disease that affects not only the women who are diagnosed, but also their friends and family. Fortunately, the last twenty years has seen a large increase in breast cancer awareness and research. This research has lead to an increase in treatment options. Herceptin is one of those newer breast cancer drugs. It was approved in 1998 and has been shown to increase patient survival times and lower death rates. It was originally designed for use in women with advanced stages of breast cancer, but has recently shown promise for those with earlier stages of breast cancer as well.
Herceptin is not effective for all women with breast cancer. It is actually designed to battle those cancer cells that have extra copies of the protein HER2 (human epidermal growth factor receptor 2). HER2 is a protein key to regulating cell growth. When HER2 proteins are altered, extra receptors are often produced, which then leads to increased cell growth and reproduction. This overgrowth and reproduction often leads to aggressive breast cancer cells, which may be more resistant to normal breast cancer treatments.
That's where Herceptin, a monoclonal antibody, comes in. Herceptin targets those breast cancer cells that are overexpressing the HER2 protein. It binds to the HER2 receptors on the surface of the cells and slows the growth and spread of those breast cancer tumors. Since twenty to thirty percent of breast cancers contain cells with overexpressed HER2 proteins, Herceptin is a significant addition to traditional breast cancer treatment options. Currently it is FDA approved to treat women with advanced HER2 positive breast cancer. However, there are clinical trials in place to investigate its use in earlier stages of breast cancer.
In early spring of 2005, the National Cancer Institute announced its research had shown dramatic results when Herceptin was as part of a treatment plan for women with early stage HER2 positive breast cancer. In this study, women were initially treated with surgery to remove the main tumor, followed by either chemotherapy or chemotherapy plus Herceptin. Those women who received the Herceptin showed a fifty-two percent decrease in reoccurrence of the cancer and as statistically significant increase in survival rates, as compared to those women who only received the chemotherapy treatment.
The reason Herceptin is not being used as a normal course of treatment in all HER2 positive breast cancers is because of the potential heart-related side effects. While those women with advanced stages of breast cancer are also subject to these side effects, it is generally accepted that the benefits outweigh the risks. For women with earlier stages of breast cancer, however, that may not be true. According to the study above, Herceptin increases a patient's risk of congestive heart failure to three or four percent, while regular chemotherapy has a risk of less than one percent.
Nonetheless, the use of Herceptin in women with early stages of HER2 breast cancer needs to be investigated further. Because this type of cancer can be more aggressive and more resistant to traditional treatments, any extra edge must be fully investigated.