How often do mammograms miss breast cancer?

Little less than 10%: The miss rate is a little less than 10% but that number changes with a number of factors. Younger women tend to have dense breast tissue and have a higher miss rate. Much older women have a better rate because of more fatty tissue. Mri is too sensitive and leads to many findings that are not cancer. The key point is if you have a mass or change in the breast a mammogram is not enough to be sure.

Approximately 10%: Mammograms are the best, most cost-effective method for identifying non-palpable breast cancers, but are by no means perfect. Some cancers (infiltrating lobular) are very difficult to see on mammography. Furthermore, some women have very dense breast tissue that obscures visualization of a cancer. Therefore, a normal mammogram should never determine how to evaluate a palpable breat lump.

They can: About 15% of breast cancers won't show on a mammogram, so if you have a lump, a negative mammogram doesn't completely rule out cancer. Ultrasound can also be helpful, and sometimes a biopsy is recommended even if the imaging is negative, depending on other factors.