Your Breast Cancer Survival Guide
The Different Types of Breast Cancer
About 60 percent of breast cancer patients have hormone- sensitive tumors fueled by estrogen and/or progesterone. Around 25 percent have a deadlier type with too much of the protein HER2. (Some cancers are hormone sensitive and HER2 positive.) Younger women are likelier to have a particularly difficult to treat cancer called a triple negative -- it's neither estrogen sensitive, progesterone sensitive nor HER2 positive. There have been important developments to help all three:
Hormone-responsive cancer. More than half the drop in breast cancer deaths is due to tamoxifen, a postsurgery drug that squelches hormones that can drive tumor growth. "Tamoxifen is probably the biggest home run we've hit in breast cancer," says Dr. Berry. Tamoxifen has serious side effects, however: increased risk of uterine cancer, hot flashes, vaginal bleeding, and blood clots -- and it can lose effectiveness after five years. In tests, three newer estrogen-blocking aromatase inhibitors -- Femara, Arimidex, and Aromasin -- offer the same or better protection.
HER2 cancer. The HER2 protein triggers the unchecked growth of cancer cells, creating a particularly aggressive form of breast cancer. Herceptin, a drug that stops the action of the protein, plus chemotherapy, more than halved the risk of recurrence in early, and operable, breast cancer and reduced death by about 30 percent. That should save 250,000 women annually diagnosed worldwide.
"What's even better is that there are newer experimental drugs that are every bit as effective as Herceptin," says Dr. Hortobagyi. In June a study showed that when a new drug called Tykerb was taken in combination with the chemo drug Xeloda by women who had previously taken Herceptin, it nearly doubled the time it took for breast cancer to grow or advance, compared with taking Xeloda alone. If it is approved by the FDA, Tykerb could be available in 2007. What's more, Tykerb is a pill, while Herceptin is taken intravenously.
Triple-negative cancer. There's hope from a traditional cancer medication that is now being studied for breast cancer treatment: Avastin, a colon cancer drug that, combined with standard chemotherapy, nearly doubled the time patients with advanced breast cancer lived without a progression compared with those who had chemotherapy without it.