Benign simply means noncancerous and malignant meaning cancer of the breast.  Most lumps and breast concerns that we see are benign breast disease.  Only a small portion of our patients are ultimately diagnosed with malignant disease (breast cancer).  It is our job to determine what breast problems stem from cancer and which problems are not cancers.  This can be challenging, but we use our physical exam in conjunction with mammography, US or MRI to help us make that differentiation.  Sometimes we need a biopsy to discriminate between the two.  We obtain a small sample of tissue and is analyzed for cancer cells.  Some noncancerous (benign) conditions can be easily diagnosed without a biopsy, but if there is ever a question, a biopsy will be recommended.