Can a 57 year old woman have breast cancer if last mammogram was 1.5 years ago and normal? never had an abnormal mammogram. what stage cancer?

Absolutely: Breast cancers arise from normal breast, and they can grow fast. And i can't tell you the stage of the cancer. Hopefully it is still contained. If you have an abnormal mammogram, you need to get a tissue diagnosis. It may be benign. If it's cancer, definitively treatment is much more likely than not to save your life. Do what you know you must.

Yes: The normal mammograms in the past won't protect you from future breast cancer. Also, mammograms are about 80% sensitive for detecting cancer, so 20% of cancers won't be seen. 1.5 years is enough time for a cancer to double in size 6 times. If you have a lump, see your doctor. If not, please resume your screening mammography.