What does a shadow on a mammogram mean?

Many things: A shadow on the mammogram could represent normal breast tissue, overgrown breast tissue, a benign tumor, a cyst, or a breast cancer, among other things. Sometimes your doctor may order additional mammogram views or an ultrasound to get a different view of the area.

Mammogram: Anything above the density of fat, including normal fibroglandular breast tissue, shows up as a "shadow" on a mammogram. The shape and the margins of the shadow are among the features of the shadow that determine if it is suspicious and/or requires additional evaluation.