For example, an ultrasound is better at differentiating between a
mass that is solid or fluid filled. A solid
mass on ultrasound may not show up. On mammogram certain characteristics can show up such as microcalcifications, or a density, but it too has its limitations.If you are too concerned about this lump,ask your doctor,who has the all the details about your case, to consider if a biopsy would be necessary to find out the nature of this lump.Best wishes .