Researchers: Not all Cancer Cells Can Spread

Researchers who studied breast cancer say they can tell which cancer cells are the most dangerous -- the ones that will spread. The researchers found that only a minority of breast cancer cells have that ability.

They say these cells were able to develop into various types of cells found in tumors. The scientists also spotted parts of the surfaces of these cells which made them different. Those areas are targets for development of cancer-killer therapies that would focus just on the dangerous cells.

The researchers are at the University of Michigan. The study is in Proceedings of the National Academy of Sciences.