Narrator: This is Science Today. A drug therapy that blocks the formation of new blood vessels will be tested nationwide in a new breast cancer trial. Dr. Laura Esserman, Director of the University of California, San Francisco Breast Cancer Center - which is one of the sites participating in this study - says the process of new blood vessel growth is known as angiogenesis.
Esserman: Tumors can't get big if they don't have food and food comes from the blood. And there's specific ways in which tumors recruit the growth of blood vessels to help support them - it's like they're building roads to themselves so they can get supplies in. So the idea is, if you can block the road or destroy the roads or the bridges, that you can stop tumors from growing.
Narrator: The ultimate goal of the study is to determine whether an anti-angiogenic agent can effectively starve tumors in women with earlier stages of breast cancer.
Esserman: We ought to be able to see that and quantify it so that we could have that as a target - say, instead of waiting to see whether people die or don't die, that we can say, well we can see it has an impact on the tumor.
Narrator: For Science Today, I'm Larissa Branin.