The statistics are comforting and well-known: When breast cancer is detected and treated in its early stages, 86% or more of women survive at least five years.
What about women who have advanced breast cancer? What about women who are diagnosed with Stage III breast cancer, in which a number of lymph nodes may be affected, or metastatic breast cancer (Stage IV) that has spread to other parts of the body?
Tamoxifen is a medication that blocks the action of the female hormone estrogen in the body. For more than 30 years, doctors have prescribed tamoxifen to fight tumor growth in women who have breast cancer with tumors that are fueled by estrogen. Tamoxifen was the first selective estrogen receptor modulator (SERM) to be approved by the FDA for both prevention and treatment of breast cancer in high-risk women.
Without doubt, they face a tougher battle. Yet medical research is making strides in their care. Indeed, women with Stage III breast cancers currently have a 49% to 56% chance of surviving five years, while women diagnosed with metastatic breast cancer -- once considered hopeless -- now have a 16% chance of surviving five years. Moreover, new treatments being tested offer great hope that these women may soon live longer and better lives.
To understand the gains in treating later-stage breast cancer WebMD turned to three prominent oncologists: Claudine Isaacs, MD, co-director of the breast cancer program at Georgetown University Medical Center; Edith Perez, MD, professor of medicine at the Mayo Medical School in Jacksonville, Florida; and, Jonathan Serody, MD, an associate professor of medicine and researcher at the University of North Carolina's Lineberger Comprehensive Cancer Center.
Here's their summary of drugs offering hope on the horizon:
The biggest news today for women with advanced breast cancer is a drug called Herceptin. No other treatment in recent years has done as much to prolong the lives of women with later-stage disease: In a study published in the New England Journal of Medicine, Herceptin improved the average survival time for women with Stage IV HER2-positive disease from 20 months to 25 months. That's the most significant improvement in survival for these women that's been seen in a long time.
Herceptin is one of a new class of drugs called monoclonal antibodies -- lab-engineered antibodies designed to mimic the body's own immune system response. Herceptin targets the HER2 protein, which, when it's overproduced in breast cells, leads to the proliferation of abnormal cells or cancer. When the drug finds HER2 proteins on the surface of the tumor cell, it binds to them and either kills the cancerous cells outright or stops their proliferation.
Herceptin is only effective in the 20%-30% of women whose cancers involve overproduction of the HER2 protein. Still, for these women, "Herceptin has improved survival rates more than anything else," says Claudine Isaacs, MD, associate professor of medicine and oncology at Georgetown University Medical Center and co-director of the breast cancer program. Herceptin is representative of a new approach to treating advanced breast cancer, and more monoclonal antibodies are in development that will target other causes of the disease. For instance, researchers are now looking at several drugs that are designed to affect another protein involved in some types of breast cancer called HER1, or more commonly, EGFR. While initial results haven't been especially positive, researchers are still hopeful that further study of EGFR-targeting drugs will be more successful.