Question: What is Avastin and when might it be used?
Answer: The drug Avastin is a monoclonal antibody that targets a particular protein called VEGF, a small protein that plays a very major role in the development of new blood vessels.
One of the things that cancers have to do is to grow, and then, to spread. For a tumor to grow, and also for it to set up housekeeping in a new organ, it will have to develop a blood supply. VEGF is a protein that is critical in this particular process, and the antibody Avastin (or 'bevacizumab') is an agent that targets that particular protein. Again, in trials in metastatic breast cancer, it has been shown that Avastin has some anti-cancer activity by itself; it has been shown that it can improve outcome when added to traditional chemotherapy in women with advanced breast cancer. Studies will begin shortly to look at whether or not Avastin should be used in the setting of earlier stages of breast cancer, particularly lymph node-positive breast cancer, in conjunction with chemotherapy.
One of the very exciting things about Avastin is that its effects are not limited to breast cancer; in fact it has utility in several other kinds of cancers -- including colon cancer, lung cancer, kidney cancer, and ovary cancer -- and this is probably because it attacks a very basic mechanism that is important to a multitude of cancers.
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