A new study could change the way women are treated for breast cancer.
British researchers have reclassified breast cancer into ten different categories based on the genetic makeup of a tumor.
That means scientists can now identify the specific genes causing each woman's disease and will allow for more individual and personalized treatment options.
Researchers say by pinpointing the biological cause of each tumor, they know which drugs it will respond to.
The discovery won't affect women who have breast cancer right now, but it could change the course of treatment for patients in the future.