1. A method for use in a computer system comprising one or more processors performing the steps of: obtaining a plurality of x-ray tomosynthesis projection images of a patient's breast; generating a three dimensional reconstruction of the patient's breast using the x-ray projection images; synthesizing a two-dimensional mammogram using at least a subset of the plurality of x-ray tomosynthesis projection images, including re-projecting at least a portion of the three dimensional reconstruction onto a two-dimensional image; and displaying the synthesized mammogram on a display device.