Dear bd728, It is difficult to say what they are referring to without more information. It may be one area that is more lobulated as seen on an ultrasound, or perhaps they are referring to a cluster of microcalcifications seen on a mammogram. The decision for type of surgery is based on many factors including size of tumor, location, whether there is multifocal disease (involving more than one area in the breast), as well as cosmetic considerations.
With the above mentioned 3 cases of breast cancer in the family, another item you may want to consider is a consultation with a genetics counselor experienced in hereditary breast cancers. These professionals usually can be found in large academic centers.