Mammograms expose you to low-dose radiation. The dose is very low, though, and for most people the benefits of regular mammograms outweigh the risks posed by this amount of radiation.
Having a mammogram may lead to additional imaging. If an area of concern is detected on your mammogram, you may need other imaging. These might include additional imaging such as specialized mammographic views, ultrasound, and a procedure (biopsy) to remove a sample of breast tissue for laboratory testing. However, most findings detected on mammograms aren't cancer.
If your mammogram detects an area of concern, the doctor who interprets the images (radiologist) will want to compare it with previous mammograms. If you have had mammograms performed elsewhere, your radiologist will ask for your permission to request them from your previous health care providers.
Screening mammography can't detect all cancers. Some cancers detected by physical examination may not be seen on the mammogram. A cancer may be missed if it's too small or is located in an area that is difficult to view by mammography, such as your armpit.
Not all of the cancers found by mammography can be cured. Some breast cancers are aggressive, grow rapidly and quickly spread to other parts of the body.