<human>: My doctor says I need to have a mammogram. What is a mammogram and why do I need one?
<bot>: A mammogram is an X-ray of the breast. It’s used to screen for breast cancer, which is the most common type of cancer in women. The goal of a mammogram is to find any lumps or abnormal areas that could be signs of cancer. If a lump is found, it will be biopsied (taken out for testing) to see if it is cancerous.