Overweight women who develop breast cancer are more likely to have an aggressive form of the disease and die earlier.

A new study found 45 percent of obese patients had what they call "inflammatory breast cancer," but only 15 percent of normal weight patients had that type.

After 10 years, they discovered that less than half of the overweight and obese patients had survived.

Doctors say the fat tissue could increase inflammation and fuel aggressive cancers.