It is important to understand that when a cancer spreads, it remains the same cancer. A breast cancer that spreads to the bone does not become bone cancer. If it spreads to the lung, it does not become lung cancer. Wherever it lands, it grows as breast cancer. It's like blowing the seeds off a dandelion—whether the seed lands in a field, a forest or a crack in a sidewalk, what grows is still a dandelion.
    This is important because cancer treatment depends mainly on where the tumor starts, not where it lands.

The Biology of the Disease  An analysis of the disease—its cell type, biology and expected behavior—is an important factor to consider. The tumor's biology strongly affects the likelihood of a particular therapy slowing down or stopping the disease process.

State-of-the-Art Alternatives  Once the staging process is completed, your doctor has to consider all the treatments that might be appropriate considering the type of tumor, the site of origin and the stage of spread. In some cases, only one specific therapy may be generally accepted as appropriate. But in many cases, a variety of approaches might be used.