Dana-Farber Cancer Institute, Boston, Massachusetts

Over the past ten years we've come to understand that breast cancer isn't one disease, it's a family of diseases. And we use that information when we provide advice to new patients who are diagnosed with breast cancer and we use it when we think about breast cancer research.

At Dana Farber we have over 40 physicians who spend all of their time either taking care of women and occasionally men with breast cancer or on breast cancer clinical research.

We have an equal number of individuals, if not larger, who are based in our laboratories trying to understand the molecular workings of breast cancer -- why some cancer cells grow and flourish and others don't seem to cause the same difficulties for a woman.

With a group that size we're interested in many different aspects of breast cancer, but there are two areas in particular that we've tended to focus on. One is what's called HER2-positive breast cancer. This is a subtype of breast cancer that affects somewhere in the range of 30,000 women in the United States each year.

In the past it was thought to be a particularly aggressive type of breast cancer; but more recently there are new drugs, drugs like Herceptin and Tykerb that can be effective for the treatment of HER2 positive breast cancer. But we know that these drugs don't work all the time and that sometimes they stop working. And with our colleagues in the laboratory we're trying to understand where these drugs work best and where we need even better therapies.

The other area we've tended to focus on is what's called triple-negative breast cancer. This is an even less common subtype of breast cancer but it still affects somewhere in the range of 20,000-25,000 women each year.

For women who have triple-negative breast cancer chemotherapy can be quite effective but it clearly doesn't work all of the time and there are patients for whom it barely seems to work at all. And once more with our colleagues in the laboratory we are trying to go back and forth from the laboratory to the clinic to develop new and better therapies for these women and for all women who have breast cancer.